Sony does not own the rights to the original FF7 as far as I know. Square-Enix can do with it as they please.
Vesperia and Lost Odyssey maybe would've done better on the PS3 but probably not that much better. Blue Dragon is a franchise that likely would do best on the Wii, neither Sony or MS have shown they can market/sell any type of game with a more cartoony style on the HD consoles.