I'm glad to see more female characters, and adding more would be a good idea, particularly since there isn't exactly a shortage of them in the series. I'll be picking this one up. I loved the first one, and the I expect a similar level of quality from the first.
I suppose I should go on and say who I'm hoping for in the sequel:
I don't know the earlier games (1-3) all that well but here goes on the rest:
Final Fantasy IV - I'd like Zemus for a new villain and Rydia as a new playable character, though there would need to be mechanics in place to distinguish her from Terra in terms of play style.
Final Fantasy V - Gilgamesh is the obvious choice for villains. I don't really care all that much which hero is put in, though.
Final Fantasy VI - Locke or Celes is the what I believe the best choice is for this one. Give Locke one of his boomerang-esque tools and I'd lean towards him. Other villains would be hard to do. General Leo would be a possibility if it weren't for him not exactly being evil. If it was Celes then they could tie in an interesting story there, though.
Final Fantasy VII - Tifa or Red XIII for hero. Both, I think, would have playstyles I'd enjoy. Plus, it'd be nice to try out someone quadropedal. If Red was chosen then I'd say Hojo should be made the new villain. If Tifa was chosen, then I'd say Jenova, though they'd have to work with the design a bit to make her... humanoid.
Final Fantasy IX - Freya, Vivi or Garnet is what I'm hoping for. Garland is the obvious choice for a new villain, but he shares a name with another villain. If there was a distinction made, he'd be the perfect choice.
Final Fantasy X - I didn't care for in terms of characters. I'd be perfectly happy with no one new. Then again, I'd love to kick the crap out of Seymour a bit more, he being atrociously annoying. If they're adding a new hero, as long as it isn't Wakka I'll be alright with it... I guess.
Final Fantasy XII - I didn't care for the cast of this game either. Balthier would be a good choice, I feel, though. Dr. Cid would be the best choice of villain, as well, particularly with Balthier's relationship to him.
Final Fantasy XIII - I was glad to see Lightning joined the cast. Not that I particularly liked her, but I'm happy to see another female character (I would have preferred Fang, though) and I feel like I would enjoy playing as her. Cid Raines could make a decent villain. I suppose Barthandelus(sp?) could work in his human form, but I found him a little bit too one-dimensional, even for a Final Fantasy villain.
and, for god's sake!!!
Final Fantasy Tactics - Ramza is the obvious choice for hero, but I would be perfectly happy with Delita, Zalbag, Agrias, etc. Villains also have a lot to choose from: Altima, Vormav, Weigraf, Algus, Dycedarg.
Here are my ideal match-ups for what I assume would make the best story:
Hero: Ramza Villain: Weigraf
Hero: Delita (pre-holy knight. Holy Knight could be alt. costume) Villain: Algus
Hero: Agrias Villain: Gafgarion
Hero Zalbag Villain: Dycedarg
I would be happy with ANY characters from that game, though... Please?