Idea for an Aatrox Ultimate

I'm just gonna pitch it out there to see if it sounds balanced or not.

So here is the ultimate: A percent of Aatrox's damage is transferred to his nearby allies as healing for a set duration of time. He could probably still be given the extra range, but either the attack speed or initial damage will probably need to get cut to make it balanced.

A lot of people say that Aatrox should've had Sion's old ultimate of the AOE life steal. It does fit his theme but the ability itself is unhealthy because it is an aura and nothing can be done to stop it. So how do we fix that? By giving it conditions and options to stop it.

Right now Aatrox is split between two identities; the AD support-ish battle commander type champion that empowers his allies through buffs that a lot of the community wants, and the life drain diver kit that he as made with. I think this ultimate is a pretty healthy combination of the two identities that seems fairly balanced (at least on paper). Aatrox can have the high points where he just completely saves a team fight by jumping in at the right time and sustains his whole team through a super close fight, but Aatrox can also have the lows where he jumps in and gets nuked without doing anything. Do you guys think this is a healthy base idea for an ultimate?