it's so hard because thankfully, all the party characters pique my humble interest this time (unlike some games, no matter how great, i could still pick out the ones i wouldn't put in my party)...but definitely a Vaan and Balflear team, and as much as i wanna put Ashe in, probably Fran or Penelo, because there have already been "female knight" types (Agrias, Meliadoul), and decidedly rarer main assassin-dancer-ninja types like Fran or Penelo.

btw, in the english version will it be Balflear or Balthier? i hope it's balflear