Great!
A few areas it can improve:
1. When I get the upgrades that give me coins when I kill a thing, the coin notifications get in the way of a bunch of guys I want to click and I have to navigate around them. Would be nice if those were more subtle or could be clicked through or they didn't obscure the board. Also, if I die and restart, but a bunch of notifications are queued up, they still keep popping up.
2. I would like a feature to export my save. I'm not sure if it will transfer if I log in on another computer (on vacation and haven't tried yet/just made an itch.io account).
3. Small thing as a first time player is that I didn't like that I had to die if I wanted to return to the main menu/restart. Not a huge problem for gameplay, I just think it would give new players less friction when starting.