Have some trouble grasping how this is going to work in practice.
My main is Druid and I will play Resto end-game, so that's the artifact I would need to pick.
But I'd assume leveling as Resto would pose a lot of challenges and at the least would be sub optimal so I'd be Balance when questing. Assuming no weapons drop that'd be getting harder and harder as levels progress as well. moreover, are there rewards in game when question tied to the artifact of the spec you're playing?