Letting Fayris use spears is kind of a waste since she starts with high dagger skill and there are some very good daggers in the game. Letting her spam Lightning if she's not using the bow (craft her the perfect soul bow) is best anyway.
Cano should spam Stars if ranged is needed. It recharges very quickly; otherwise he's more suited to throwing weapons.
Best axe is spectacular, you get it in a sidequest.