Trying to decide a critical factor for how the player progresses through the game

I’m trying to figure out the way you move between levels, and I have discovered that certain ideas I have for my game are in conflict with each other.
I’m not expecting anyone to solve this for me, but maybe just laying everything out can help me sort things out.

My game has simple arcade-like level design. Each stage is relatively short, you clear a stage, you move on to the next stage.
I was thinking originally to have a level select screen (map); complete a stage, unlock the next one, that way you can also review your score for each stage, go back to old stages and replay them to get a higher score.
Pretty standard stuff.

But I have also been working on a small inventory system where you can get certain (consumable) items to use at your discretion. Some would allow for offensive capabilities in a game that otherwise doesn’t allow attacking, or temporary power-ups and boosts. You’d only be able to hold three at a time, and they are in limited supply, and they carry over between stages. Basically, use them to get yourself out of a tight spot, or to maximize your score.

But the problem is: if these items carry over between stages, and you can select your stage from a map, then you could just go back to earlier stages and just farm items. This destroys the scarcity; if you want that one really powerful weapon you just go back to that stage and pick it up again. Whereas it was supposed to be something you can get just a couple times, a powerful weapon to be reserved for the most dire need.

So my item system was designed more around the idea of linear progression; you complete a stage, you move on to the next stage. No going back.
It does invoke a more classic arcade style, which is nice, but that would also put off some players. Plus, now I have to put more care and balance into things like player lives, saving progress, and other things I’ve forgotten to consider.

So I’m in conflict.
Should my game just move from one stage to the next without any player input? Or should I have a level select screen where you can see you high scores and replay old stages?
Should I retain the item system I have devised? Or should I work out a new system that rebalances scarcity?

I think your progression and item system can maybe work with a replay system if you do something like this:

In “Story” mode, consumables can drop, and they can be used. You’re in “Story” mode any time you’re playing a level you haven’t finished yet. In “Replay” mode, no consumables drop, and you don’t have any consumables. You’re in “Replay” mode any time you’re replaying an earlier level you’ve already finished at least one.

I’m not sure if that would feel great or intuitive, though.

But I also think it feels odd to have these limited consumables that you use if you need some extra help, until you reach a point where you need some extra help but you’re all out of consumables. Then, for some players, the game might come to a halt, as they can’t progress without the consumables they’ve gotten used to.

Going back and grinding earlier levels is definitely a thing that many games make you do. But that feels more like a thing I’d expect from a mobile game that wants me to get impatient and purchase IAPs instead to progress faster.

What feels much more fitting with the kind of game you describe might be consumables that don’t carry over from level to level, but which perhaps require certain precise actions to get them to drop. So, while replaying a level, maybe there’s something complicated you can do to get the consumable to drop. But you need to use it on that specific replay of the level, as you don’t bring consumables with you. That would allow you to balance specific levels to allow more or less consumables to drop, depending on whether players need more help. Just an idea.

I’ve been giving it some thought, and the best plan I have is to make it so that if you change to a different level, you just lose all your stored items. Maybe I might make it so you can’t replay a level until you’ve clear the game once normally, but I’m not sure if I like that idea.

Hmm. Not bad. The only problem is that calling it “story mode” suggests that I have a story.

It would be something like you’d find maybe one item per stage, so you’d get one “get out of a tough spot” per stage. But to add depth to the gameplay, you can hold on to them to use in the next level. But I’m putting a cap of three so that people don’t just start hoarding on to them; a small limit forces players to actually use them.

You could also make “Story Mode” the only option at first, but then make replayability a “new game+” type of feature after someone finishes the game.

you could do like splunkey or enter the gungeon (I think I spelled that right) where you get random loot on every level that way you can still get a chance at something to save you on like level five even though you used your other items on level four. then that way you can’t just grind a level for the best items or so you won’t feel like there is no way to beat a level with no item because there’s that chance that you get a really good on that you can use at just the right time to survive

and after you beat the game you could get the ability to replay the game with harder bosses but better loot or like one item mode where all the items are the same.