Looking at it again I noticed something else...
As it is now the rope is on the front lower part of his neck. This would most likely cause his head to be pulled down and his body would do more of a somersault or at least swing the opposite direction since the rope is on his right side (which, incidentally, he passes right through)
If the action was slowed down and the rope was moved to the back of his neck and to the other side of his body, I think the "fall" would look pretty good. Of course that's the "easy" way to fix it. Since the rope seems to be coming from below his neck and somewhere on shore it's probably where it should be. (under his neck, right side)
Anyway, I hope that's helpful.