Graphics were good and have the MS paint feel. Love the hand drawn font too.
Could do with a few different enemy types? Or maybe I didn't get far enough into the game to see those?
Nice game.
I started making the game three days before deadline, so I have very little time to do anything.
Maybe I could add some mini-boss enemies at the end of each wave to make it more challenging.
For now I'm more focused on refining controls and collision detection.