Journey
1-3: summons slider/infinite buffs/stat slider: sure, its journey after all. Basically the equivalent of minecraft creative.
4: Auto research: This, however, is a no. What if you need the items and dont want to research it yet.
5: Auto delete: Check my incinerator suggestion, but in general I do not think this should be a feature.
6-8: Time skip/fullbright/respawn time slider: sure, its journey
9: Homing projectiles: this however is a no. It removes the skill aspect from ranged weapons, and at that point just use melee.
10: Projectile speed slider: also a no, same as above. A feature like this changes the fuctionality of weapons, which I do not think is a good idea.
11: Vein miner: no, why would you be able to instantly break many blocks at once? just use explosives at that point
12: Functional vanity: Also no as this would be harmful to new players, perhaps enable the expert mode slot for journey mode players? although dont you already get a 6th?
13: Infinite ammo: sure, as this doesnt affect the actual mechanics of the weapon, but would be a helful convenience.
14: Resistance slider: also sure
Equipment:
1: Potion bag: unnecessary. You can now store and use them from the void bag. And if youre worried about space put them in the safe instead and keep 1 safe in your void bag then,
2: Shell phone moment
3: Wormhole mirror: sure, this actually could be a cool earlyish hardmode upgrade that would NOT extend to the cellphone, but still be cool. Support.
4: Rod of harmony seems good, but havent gotten one yet. Unrelated, but I wish the hook of dissonance actually teleported you not just pulled instantly.
5: Ultrabright torch should be the brightest: agree 100%
6: Consumable guide to critter companionship: Eh, we already have too many buttons so I think its fine the way it is now. Especially since it can now be dynamically disabled in the inventory.
7: Infinite rocket belt: Maybe, as long as you mean the ones that dont break blocks.
8: Unlimited chum/unlimited master bait: No. I posted a suggestion for an endless can of worms (Infinite Can of Worms) but there definitely should NOT be an item for infinite of the best bait in the game. I would also entertain the idea of the angler having a shop and sells apprentice bait (again, NOT master bait) but I dont know what else he would sell.
9: HotChum Golden Rod: No one would ever use them indivdually if you were able to just combine them, but check out my idea for more hardmode fishing rod concepts: WIP - More Fishing Rod Concepts
10: Pulling NPCs with rods: Yes, it would be funny
11: Golden bobber: TWO HUNDRED?? Why? make it 25 and have it replace the hotline rod along with my change mentioned here: Hell Bait should not allow Lava fishing/Useful Hotline Rod
12: Unbreakable golden key: I dont agree with a master key that includes all the biome keys, but an unbreakable golden key would be nice. Although, unlike shadow keys, they do stack so... its not needed that badly.
13: Craftable altar: NO that would allow you to place it wherever you wanted which makes the demon altar feel like a regular workstation and not special anymore. Besides, isn't it common knowledge by now you just dont break them all since you need one for crafting?
14: Combinable banners: I think theyre working on this actually, but a placable "banner rack" could be cool.
15: Water candle debuff: I think it would be best simply making the candle equipable: Equipable Water Candle
16: Ultrabrght torch again: yes I do think it should be brighter
17: Pocket base: I dont think I fully understand this suggestion, but if you mean instantly uploading a base build from one world to another, definitely no.
18: Teleport to pylons without being near one: honestly this is something I think should be vanilla behavior of the cellphone (no need to add another item), and I use a mod that adds it.
19: Ultra buff station: I do not think they should be able to be combined for the same reason as 9. Besides theyre PERMANENT buffs that last until death. You can suffer through clicking 5 times instead of 1.
20: Quicker explosives: How about a type of bomb/dynamite rather than a new item: so normal, sticky, bouncy, quick (I picture it as green maybe)?
21: Horn o' Plenty: What do you mean unlimited? How about an equippable that gives permanent well fed as long as it is equipped (and for 3 minutes after)
22: Poo Solution: I assume this is a joke, so no.
23: Indestructable paint: sure, why not
24: Asphalt platform: No, you sacrifice mobility for speed.
25: Super sugar rush cake: How about make the current slice of cake a consumable food item instead that grants speed for 8-10 minutes (since you eat the whole thing) and the current buff station is now purchased during a party for like 10 gold and gives the current boost of only 3 minutes (since you only take a bite)
Weapons:
1: Zenith+Teraprisma+Keleidoscope: Are you suggesting a multi class item? The zenith is already OP enough.
2: Railgun: sure why not.
3: Golden Wrath: I dont really see any reason to combine the two.
4: Ichor Rod: This would be a funny idea, having a yellow cloud to match the other two
5: Wall of cursed flames: sure, taller is better
6: Cursed Inferno fork: Longer aoe? sure, why not.
7: Broken Hero Weapon: Um, it defintely shouldnt be a wepon of its own, but maybe you should be able to restore it into a weapon? Perhaps with hallowed bars, but at that point just add it to the excalibur recipe.
8: Lucy the ham axe: I dont really think this is neccessary.
9: Possessed Knives: Sure why not. Perhaps in order to balance it, the healing would have to be nerfed/removed, but still a good idea.
10: Lifesteal summon: agree
11: Kazikli Bey: sure
12: Flare Gun MKII: I assume you're looking for an increased fire rate? I dont really think this is necessary since late game I use the clentaminator to light areas.
13: I dont play elden ring: idk
14: Acorn gun: lol sure
15: Town slime staff: that summons a random town slime you have already found? sure
16: Terraformer: Why would it deal damage? Maybe a new "acid" solution that does? Reforges would be okay too I guess, but unneccessary
18: Rocket Drill: I do not support an item that converts regular rockets into ones that destroy tiles.
19: Bunny launcher: lol also sure
20: Endgame pickaxe: Agree with the hamaxe thing, but I dont think combining them is a good idea.
21: Parry: I feel like this is unncessary but maybe?
22: Frost Whip: Yes
23: Vampire frog/vampire bat lifesteal: sure, but same as 10
24: Slap boulders/Block rain with umbrella: Yes
25: Chainsaw man: Never seen it, but just make butchers chainsaw equipable in the head slot?
Armor:
1: Modifiers: Yes, sure. But hopefully unique ones like outlined in this post here:
2: Space viking armor: No, becuase stardust armor is already endgame. Lucky for you, as of 1.4.4, it now gives a bonus sentry in addition to summons.
3: Rain set: support
4: Moon Lord's Torso: Sure, but only on some special seed or something.
5: Functional Vanity Armor: Again, just like accessories, no. If you want the mining/fishing boost, then boo-hoo, you take the defense that comes with it. Perhaps though there could be a hardmode upgrade.
6: Change fishing set bonus: No, there are already tons of ways to get fishing power: rods/baits/chum/even potions, it would be boring to slap that onto the armor too. Plus, I like how I can fish in peace and not get attacked as much. If youre intentially trying to mob farm, then dont use the fishing gear. Simple as that.
7: Creeper works in vanity: same as 5. Maybe this explode on death behavior could also be an accessory too? But definitely not from vanity.
8: True Hallowed Armor: Maybe I guess but I dont really see a reason to add it.
9: True Red's Armor: Again, maybe in a secret seed.
Accessories:
1: Magnet ring: I had this exact same idea a while ago, so yes, support.
2: Midas Hand: Seems unneccessary and needlessly complicated.
3: Tera Shield: I guess so. I assume this is solely to combine stats?
4: Super Paladins Shield: Seems unneccessary, although admittedly I dont have friends so this never comes into play.
5: Pixel change on ankh shield: Support
6: Aegis: You should probably put this before the tera shield suggestion, but on its own? Sure. Inflictes scared and makes most basic enemies move away from you.
7: Celestial Shield: It has been suggested many times that the Celestial Shell should be able to be combined with the ankh shield, but I agree that this would be OP and should not be added. But as if that wasnt op enough you throw in a master mode exclusive moon lord drop? XD
8: Combining Expert mode accessories: Sure I guess? I dont play expert mode.
9: True YoYo Bag: Sure, I don't see why they shouldn't be combined.
10: Summons inflict fire: sure, sounds good to me
11: Putrid Scarab for summoners: sure
12: Distract enemies: Im sure something balanced could be figured out. I had an idea that summons should do this (but would have to have health): Summons should have health/distract enemies
13: Ichor stones: thats basically free permanent bonus damage and seems kind of op.
14: Cursed Inferno stuff: sure why not
15: Debuff stones: No but I did share a suggestion for throwable debuff potions: Throwable Potions
16: Old Ones Army gear combination: Seems Op, but I dont do Old Ones Army that much or use any of that armor so I should probably not make a decision on this one.
17: Dune Rider ability stays on terraspark boots: NO, first of all, becuase what if you crafted terraspark boots with one of the others, and also if you want the dune rider ability... just use the dune rider boots. Same with the flame walker boots. I'm glad my terraspark boots dont have a fire trail everywhere. Maybe this functional fire trail could be added as a separate upgrade.
18: Celestial Shellboard: No. Read number 7.
19: Super Bee combination: No. These items are way too unrelated and random, even if they are all bee themed.
20: Ninja turtle gear: This is another thing Ive seen suggested, and completely support.
21: Teraballoon: Maybe, but there is already the bundle of balloons.
22: Omerga magnet: this is another idea that a large majority of the community has wanted for a while. Support.
23: Witch doctor mask: support, perhaps dropped from him?
24: Wing slot: I have always disapproved of this idea but actually its starting to grow on me... If theres an item that is mandatory for every player, there should be a slot for it: like minecarts/hooks/pets etc, and wings fit that definition too.
25: Lifesteal accessories for other classes: maybe instead of an accessory, there could be a summon like you mentioned in weapons 10, and vampire arrows/bullets for ranger?
26: Charm of Mana: a "charm of myths" for mana sickness? support.
27: Attack wings: we already have this, its called using a weapon when flying.
28: More fishing lines: WIP - More Fishing Rod Concepts
29: Turtle shield: A good concept, but as for the thorns part, the turtle armor already has a thorns effect to my knowledge.
30: Arch Wings: Unneccessary
31: Terraspark Boots with socks: The terraspark boots are already endgame, plus the tabi can be upgraded to master ninja gear.
32: Shart stuff: ... just no
33: Arctic Diving gear should remove the mining speed penalty under water (and if I am remembering incorrectly and there isnt one, there should be) although I suppose this doesnt solve the problem as the neptunes shell would do that too... Actually, I think its fine as is.
34: Boots of Regrowth: All around a good idea. If you dont want your dirt turned to grass just dont wear them, and a passive alchemy plant collection boost seems nice. I dont know about an AOE (as in affecting blocks you dont step on). I think the current dryad boots behavior is good. Keep in mind the grass will still spread even if you dont fill it in perfectly.
Pets:
1: Jewel of Light buff: I dont play expert or master but I do see what you mean. I agree the Jewel sounds like it should have the ability to detect treasure, but 200% seems WAY too high. How about 150%? This would make it better than the tentacle.
2: Pets shouldnt produce light: Eh, i think its fine but I see your point.
3: Combined Pets: in general I dont think this is a good idea, but its too late to revert the slime one. At least it does sort of make sense.
4: All storages pet: BIGGEST NO YET. You literally just came up with the most incomprehensibly OP pet I can imagine, and you expect it to be a REGULAR pet, NOT EVEN A LIGHT ONE?? I already dont really approve of chester being a regular pet: Make Chester a "light pet" for balance reasons
5: Circling phantasmal dragon: No, this would get annoying very fast, at least the cursed sapling lands.
6: Money Trough>Chester? Then feel free to use the money trough. But some find him useful as they do not wish to give up a hotbar slot. See previous link for my thoughts on chester.
7: Chromatic Cloak equipable while in shimmer state: Maybe? But im leaning towards no becuase the whole point of shimmer is it freezes you until you fall into an open area again, and being able to edit your inventory at all during this kinda goes againt that. Shouldve equipped it before you fell in.
Minecarts:
1: RoboCat Cart: Unneccessary now that the minecart upgrade kit is consumable.
2: The Underminer: Love the name, and the molecart does admittedly seem slow on the wiki page (ive never used it), which I do think is a good thing as it gives you more control and decreases the chance of accidental worldgriefing, but a hardmode upgrade could be cool.
3: Tank Cart: sure, slower but fires explosive shots (that dont destroy blocks of course).
4: Teracart: Minus the rail laying part, the rest would be a good combination
Mounts:
1: Black spot cannonballs: Yes, makes sense
2: Superheated Truffle: Ultimate liquid mount? Yes, minus the combination with the black spot, as that wouldnt really make sense if it now shot cannonballs.
3: Drill Containment Unit Plus: NO, this is almost as bad as Pets 4. Maybe it should glow, but otherwise it is already Op enough.
4: Tera Mount: Same as above. The mount that has fastest horizontal speed should not also have the fastest vertical speed as well, PLUS the water speed boost, PLUS infinite flight, PLUS deals damage?? Just no.
5: Toilet Mount: If we get a tera mount, I hope its not this.
Grappling Hooks:
1: Endgame hook: How about something with much longer range but only 2 hooks instead of 4? Maybe a Moon Lord's Tongue hook? but the lunar hook would still be the best for all around general usage.
2: Void Hook that pulls you to nothing: Um, this would allow infinite flight so No.
3: Webslinger hook: I think ive seen this idea before but I assume the reason they dont is becuase the engine doesnt support it? but I agree it would be a cool idea. Support.
4: Hooks pull entities: Maybe this would be a mechanic better added to hooks instead of fishing rods? and all of them should do it?
5: Hook that deals knockback: on retracting maybe, sure.
Dyes:
1: Invisibility dye: No, becuase this is infinite and would make potions useless.
2: Shine Dye: Im okay with your texture glowing as long as it doesnt actually produce light for the same reason as 2.
Quality of Life:
1: More buff slots: Personally, I never hit the cap, and 44 should be way more than enough.
2: Choose Modifier: seems okay for journey.
3: Summoner Weapon Modifiers: Basically what I said about armor reforges, Completely support
4: Prefix "limit"? Not sure what you mean
5: Longer Magic "sentries": Agree, and this was apparently done already?
6: Homing Chlorophyte Arrows: Agree, Im not sure why arrows are different. Make bouncy arrows crated with pink gel instead.
7: Placable Rope coils: maybe? You can already click on rope to extend the length of it.
8: Increased Reds potion duration: A HALF HOUR? of many powerful buffs? and theyre NOT CLEARED ON SWITCHING WORLDS?? They should be becuase otherwise players are going to abuse this. Anyways, a HALF HOUR is plenty.
9: Reds potion BUFF?? read previous line. This thing does not need any more buffs.
10: Mount stealth: Sure, but definitely not the sentries gaining crits part. If they gained extra damage simply for YOU being cloaked that would be OP. The balancing factor of the extra damage is it only works once when you first attack from stealth and it takes a few seconds to go into stealth again if you wish.
11: Instant everything: Instant defeat moonlord item too? In case its not clear, No. MAYBE some sort of placable drill that gradually digs a 2x2 tunnel downwards automatically, but it would still be faster and safer to dig it yourself. Instant boss arena and houses definitely not.
12: Craftable Ice mirror: The regular magic mirror is already craftable for renewability. My suggestion for the ice mirror would be it should be crafted with the regular magic mirror plus an ice core, but as it is just a cosmetic difference, I am okay with it not being craftable.
13: Useful Calming potions: Maybe? Perhaps this could be a separate "friend of nature" buff instead?
14: Exploding boulders: Wasnt this added on that no traps seed? Also, I think this concept should be a "c4" or something instead of a boulder.
15: Exploding Poo boulders? No.
16: Permanent buffs from inventory? NO, in fact, these buffs should be tied to the workstation and removed if the station is broken to prevent keeping them in your inventory like that just to place, use, and break them again.
17: Every Boss? is it even possible to summon all of them at once since they all have conflicting summon conditions.
18: Banker NPC: Unneccessary/OP since this is basically free money. But if it was, perhaps a new NPC rather than this being added to the tax collector?
19: Annoying drops: Incinerator (personal deleter)
20: Pixels on Ankh shield: As I already said for accessory 5, support.
21: Fertile dirt: sure
22: Dev name easter eggs: Support, especially a leinfors one.
23: Obtainable tombstones: Maybe you craft them at a new stonecutter/stonemason workstation?
24: Anti random invasion event item: Maybe, but im not sure how this would work.
25: Hampster Ball trap boulder: Nah
26: Meteor Monolith: sure, as long as it's purely visual. Full moon monolith? Maybe, though the sundial/moondial exist.
27: Luck influences crit chance: support.
28: Hide vanity armor/accessories so you see your actual gear: support. I dont think this should change minecarts or mounts though as those have special behavior.
29: Inventory while dead: no. Youre dead. Just dont die.
30: Throwable dynamite bunny: Sure
31: Vanity hooks/minecarts/mounts: No, see 28
32: Summons grace period: Support
33: Christmas/Halloween: You can get them by defeating the frots/pumpkin moons respectively. Outside of maybe journey mode, this should NOT be a "setting" (with the possible exception of a secret seed...)
34: Group permanent buffs: Better solution, make them regular buffs and not permanent. See 16 for more info.
35: Buffed Pearlwood: Slightly, sure.
36: Placeable Star Rod: Maybe instead there could be a craftable "Pocket Dimension" (infinite star ammo item). And as for meteors, I saw a suggestion a while ago for a placable "meteor defense system" that prevents meteors from falling at all.
37: Cactus armor does have thorns
38: Stackable quest fish: Why would they need to? The angler only wants/accepts 1 at a time anyways. So no.
39: Toggleable bombs: just dont keep them on your hotbar. Also no
40: Faster legendary: But legendary does other things, so if you really need the extra few percent that light gives, feel free to use that instead.
41: Axe of Regrowth fertilizer? Are you suggestion that on top of instantly replanting trees it should also instantly grow them as well?? NO
42: Axe of Regrowth upgrade? IMO the current axe of regrowth is WAY too easy to craft (literally early prehardmode) and it has 150% AXE POWER?? making it tied for the second best axe in the game and on par with the LUMINITE axes?? I think the axe of regrowth should be post plantera 
43: Endgame hammer/axe: Disagree, the luminite hamaxes are meant to be the endgame one
44: Craftable Ice/Shroomerang: No, becuase then theyre way to easy to get in a way that was not initially intended.
45: Zenith YoYo: Maybe, and it would summon holographic copies of itself? to swing around the player in a circle?
46: Autofire explosives: because theyre explosives. Im glad they dont.
47: Weapon nets/rods: No. Theyre tools not weapons.
48: Rod of Discord modifiers/knockback: Unneccessary, and as for the "recall" thing, just click where you came from again.
49: Secret Seed NPCs: Idk I dont play secret seeds.
