Hmm...
Better than SFS 2, the action was a smoother, and had sound.
Some tips for improvement: Color/detail the background, overall its a little bit of work, but a big improvement.
Speed up the pace of the action. It picks up at about the middle, then pauses. A slow beginning is fine, the climax is supposed to be the most enjoyable, so maybe taking down a guy every two seconds would be a good speed.
Finally, some VARIETY, throw in some different weapons. A bat, a sword, maybe some guns, a rocket launcher, hey maybe a tank or a plane. (Shoot the plane with a rocket :D).
Sure it will take longer to make a Flash like that, but the quality would be amazing. Your definitely capable of front page, you just need to aim for it.