That's a good game! Fun and all aspects blend great with each other!
My only complaint if I may have any is that at a specific point the enemies just flood you and it's literally impossible to proceed for more than 15 seconds or so since that point, and that depends on how many rockets you can roll in a row, so you'd have to restart to keep playing :P
I think that switching to some level/wave based thing would solve that, but it wasn't too big of a deal, I enjoyed it regardless!
Great job!