Loved the art - sprite design is simple but effective, and the parallax scrolling for the background looked amazing.
As others have said, would be great to see more enemy types, but there was plenty of fun to be had in the medium to high difficulty range all the same :) would have loved it if the transition from easy to medium came a little sooner so we got to spend a little more time in that sweet spot.
I was wondering why the difficulty ramped up so harshly right at the end before I remembered the limitation for this jam - it definitely fits!