Thanks for the thoughtful feedback! A lot of what you're saying echoes some of my thoughts with things like increasing room, enemy, and weapon variety and it is my next focus as the overall game feel is getting into a decent place. You're right to focus on interesting interactions rather than just adding more for the sake of more. The original concept had a much more maze like intent for the maps, but as the game is more built out a more linear flow seems to feel better overall. As far as upgrades go I'm looking at mutator system that "evolves" ammo into new sub types leaning more into an exploration and alchemy approach rather than stat bumps/mods.