Hi,
I enjoyed playing this game, got to a score of 150 :) A few things to maybe add a little bit more spice:
- The enemies have a random speed, so they can get to you slower or faster than other enemies.
- When the player gets to a certain score their guns shoot more bullets, or just overall power-ups would be cool.
- The design is pretty bland, so you could try adding some more fancy stuff in there (although I'm not sure what engine you've used to program this game and if that's easy to do).
Some music and sound effects would really add some charm to the game.EDIT: the music fits the art, pretty simple, but I doesn't have to be a lot more than that.
Except for that it was a nice experience and I think you did a good job with this game!
-Remi