This is pretty good stuff!

[Demios]

The concept is nice, it need a bit of balancing (2nd 3rd play through specially) but otherwise its a solid base you can extend upon! There's a few nitpick I could point though:

Auto-medkit : When you use 5 missiles and you receive the Auto-medkit as the 1st optional upgrade it feel like a letdown, perhaps add a free medkit with it to make it worthwhile or ensure one spawn in the sector it spawn in?

Maps:Could the maps have their own room spawn (no missiles cost) instead of getting those in capsules/shops?

Room types: I feel there's MANY 1x1 rooms but not much anything else, the combat feel restricted by this, forcing the player to stay close to the door in case things go sour.

Other than this, this stuffis great! Think you'll add a room/world editor? That would be neato to make a lill metroidvania of our own! Or Kazio level of difficult sillyness!

[luke]

Thanks Demios - getting a free medkit with auto-medkit is a really good idea, Medkits are rare enough that the auto item can end up being a bummer. I'll put that on the list.

Re: 1x1, a lot of the rooms sorta focus on one "idea" - tried to not have too many where you're doing the same exact thing over and over (didn't 100% succeed there) - which a bit more of a risk in the bigger rooms. Anyway yeah, 1x1 is about 2/3 of them. I might try favoring larger sizes for future rooms.

Editor & mods would be cool! Definitely hope to add this at some point. The built-in editor I made for my own use is really fast to work with but probably too confusing for most - a usability-improved version would be good. I would totally dig playing user-built worlds.