This was a pretty playable game. The one thing that weighed it down was that it did get too repetitive. You might have made it so that you could move around. I guess that might in fact negate the purpose of the game. I think the designs are pretty good. It's nothing that flashy, but it'll do.
Too bad it takes so long to get an upgrade or a new weapon. The sound is pretty good. I like how there are different noises made when you destroy different enemies. The area itself could be a tad more detailed. It's pretty enjoyable for a quick play.