A few suggestions
Block off the edges of the screeen so that you cant fly out of it. Also, when you shoot a guy it makes the explosion sound like 5 times instead of just once. You should also make it so that once the laser hits a fighter dude it stops instead of plowing through like 4 of them in one shot. The death star in the background was a little pixilated, and the whole thing was really slow. It has good potential though.