Hmm, Tokiomi showing up would be pretty interesting. It would also likely change his life significantly, because he'd meet his children (I'll be playing Sakura, and I suspect Alice will play Rin) and several grandchildren, and likely find out what would happen to them in the future (i.e., Rider and Shirou would force him to promise at sword/nail point never to hand his daughter over to Zouken...).