I played your prototype a bit. Is seems you are planning a horde survival game. Currently I see three main limitations:
- The game is limited to a single screen
- There is only one weapon, and it is really slow, which is fine as an example, but does not show the game potential yet
- There is no progression of any kind
I suggest that you overcome these problems first, and release a new prototype. At that time, perhaps you can get more interesting / constructive feedback. Good luck with development!