This is my kind of game so I downloaded it some smooth buttery framerate.
Great idea to mix a wave based arena shooter with the gambling elements with the wheel. I liked the moments of anticipating, and hoping to get the full health upgrade for example. The shooting, moving, reload felt really polished.
I think some small things could help to improve my experience. For me I often got surprised that there was a bunch of enemies behind me hitting me in the back. If the enemies had grunting sounds or something it would be easier to "read" the situation and then try to adapt to it. I think similarly with enemy spawn points and level design with the rocks it all feel quite chaotic. I think chaos and reaction based shooters can work as well, but perhaps there are some things that needs to be balanced. So that there is some order in the chaoticness :)
Overall very nice game, I had alot of fun playing it!