Scepter Idea.
Other professions actually use the scepter for casting (the attacks come out of the end of the scepter and the animations are that of swinging the scepter), so no, it wouldn’t work unfortunately. Unless they introduce profesison-specific weapons.
This could work with Necromancers too, actually. Mesmer too, to some degree (maybe add a slight shield effect to the Counterspell). Not sure about Guardian, but I don’t see anything immediately wrong with it either. +1 for the creativity.