Top. mid and jungle Aatrox all fall off as the game goes on, because you don't do much in fights. This is why you either get really far ahead, or you can avoid team fighting in lieu of spilt pushing. Think Tryndamere with a few different mechanics and easier to kite. It works well against some, works not so well against others.
Also, make sure your team understands the concept of DON"T FIGHT 4v5 while Aatrox is split pushing.