A good start for a run and gun game. The guns themselves felt like they lacked a bit of oomph, I think it would've been more engaging and better for player retention to start off with easier enemies and just the pistol and then unlock the others as you play, with the other guns being much stronger than they currently are.
The graphics were fine, but pretty basic and the lighting was pretty overwhelming at times, it started to hurt my eyes after a bit with all the darkness and then bright flashes of light. It would've been good if you could've implemented bloom, rather than the "bright but dim" saturation it has now.
Overall it was pretty fun, but definitely needs polish =)