IMO Ware. Ware has been doing this for a long time, tough to tell if Ajayi's last two games are for real or an illusion. Also, what will the touches be once Arian Foster is fully healthy? I doubt Ajayi gets 20+ touches when Foster is healthy. Charles is about as healthy as it gets, and Ware still dominated snaps. I think the KC backfield will be pretty 50/50, but KC is the better team and has the better running game.
I also love Ware's upcoming schedule, particularly the next two weeks against awful run defenses. The only tough games left on the schedule are the two Denver games. If I owned both Charles and Ware, I'd feel comfortable starting both the next two weeks.