I watched ff7 advert children today for the first time. Was kinda a weird film, it was pretty short and irrelevant, mostly filled with over-the-top fight scenes on motorbikes (there were soo many homages to the actual game it was stupid).
Anyway IMO, the ultimate bad guy cannot be someone who is simply "evil just for the sake of being evil". There has to be a story or a purpose, something I like with sephiroth.