Simplicity: Very simple, just run and gun.
Fun: Controls were kind of awful. Actually really awful. You having to hold the up arrow to jump? Not just jump higher, but jump at all. Also, maybe the bullets shouldn't be a child of the player.
Creativity: Creative story and concept, not too creative of mechanic.
Visuals: The UI is great, but you know how the game itself is.
Sound: Great music. Really adds to the game, rather than just being there.
On topic: Don't know which AI you are cooperating with. Because you play as the AI.
Great job going through the effort of a leaderboard.