FFI: Fighter
FF2&3: Did not play far enough into them to know.
FF4: Kain for battle, Edgar for comedy.
FF5:
FF6: My memory is awesome and I don't remember. I'mma say Shadow because he came to mind first.
FF7: Cid
FF8: Laguna
FF9: Uuuhhhmmm... I can't choose one D=
FF10: Auron

That's about as far as I can go.