Fair, although it feels like there's almost no reason to stand still when you have to move around to collect resources, when the enemies are as fast as they are and when you're incredibly fragile.
Interesting that more ammo increases your fire rate. I had noticed that but I wasn't sure what was causing it, so I figured it was linked to scale progress somehow. If you wanna stick with that, I might also suggest increasing reload speed; at some point high fire rates become marginally impactful.
Great work regardless!