if only...
The presentation / game style were quite awesome, including the general game play mechanics - some enemies were inventive to... BUT: It looked like the enemies were scribbled down in 2 seconds by a 4 year old (No offence, of course) If the actual drawings were better looking (instead of evil green smileys with guns and big squares that flash) this game would be TRULY awesome.
That's really all it's missing. Maybe some more detailed backgrounds too. (If you're going to see the same thing 50 times it may as well look impressive)