Had a very good time playing. the core gameplay is very very good. the dash and fireball feel excellent
there's some bugs where waves wouldn't end and i'd have to restart completely.
the death mechanic makes the game worse imo, as the best way to use it is to wait until the end of a wave, let one enemy kill you and respawn at full health. and also if you die in the middle of a fight, you're just going to get shot to death while carrying the body. going all the way back to wave 1 is also frustrating.
in terms of gameplay, i'd definitely make the fireball go in the direction you're pointing as i constantly fired it off to the side. I reckon it should not recover unless you're hitting enemies as you can cheese fights by running away and fireballing, which is lame but effective.
great job :)