Damn!! :(
SO MUCH POTENTIAL!!! The greatest and most powerful tool in animation is your timing. The 'back flip kick' was totally unnecessary, more so there was no sound or emotion. That was you main punch line so next time something like that happens do this:
"Justin Beiber"
*guy gets immediate angry face* half a second later punches the friend*
*Dragon Ball Z power sound* or something
Of coarse this is only a suggestion. You're going to have to make up your own god damn mind if you're going to accept what I have to tell you or not. :)
Good luck in future productions man!