This is a lot of fun! There are some really creative weapons and upgrades. The Flail was my favorite, but I got my high score with Ranged + Dash.
A couple of suggestions: I felt that the countdown after choosing an upgrade interrupted the flow of the game a bit too much, and I personally didn't think it was really necessary. I also think the hit feedback could be clearer when there are lots of enemies surrounding you.
Overall, really great game!