Awesome demo! Love the art and model.
Some things I want to say:
Optimization is one of the weaker points. My fps were always 60+ only when I set the rendering quality at 50%
Gun controls weren't obvious and were pretty hard to use for me (I'd put them on keys that can be easily accessed with the thumb like X, C and V. Also F isn't utilized somehow?).
Would be nice to see something like an infinite rougelike mode.
Anyway, I for sure will play a full version of this.