Originality is a terrible way to rate FF villains. Every single one of them is based on existing archetypes that have been around for years. Power levels, too, is a terrible way to rate villains. A villain only needs enough power to be a threat to the protagonists. Hannibal Lecter can't cause anywhere near the amount of shear destruction as say Majin Buu, but I seriously doubt that anyone would say Buu is a superior villain. The success of a villain should be based primarily on how well they antagonize the protagonists, how well developed their character is and how well they are integrated into the plot.

Just thought I should make that point, since I've seen a lot of these sorts of discussions devolve into 'X is more powerful then Y' or 'Y is more original than Z' on various other forums, which to me seems like a waste of everyone's time.