I'm taking the middle ground, too. Most of the characters are likable in some way. But if one has to choose, I go for Yuffie, since she annoys me too much when you first get her. She does improve, as do some of the others, but it's her cockiness which gets to me.
I agree with the mog body ruining Cait Sith....then again, what else would you like to see? Feline knight on a chocobo? Hmm. That'd make a good summon.
I noticed noone went for Cloud or Cid....and with good reason