nice! i like your design style.
seems like you could add some scoring system and a longer sequence of generated levels and it would be a wrapped up game.
did you have any other development plans/ideas?
a gameplay complaint i have to mention is the mouse going off the edge can be frustrating. could it be locked somehow or fullscreen could help this..
also, if its a small room game maybe you can get away with more debris like if the enemy bits didn't fade away when they died?
oh also also the movement burst sprite get really big if you move quickly maybe you could cap it at a certain point, just a nitpick.