In hindsight, I'm not sure there ever should have been an Arcane power source. I mean what is that really but a sacred cow mish-mash of other power sources already present or in the waiting? I think I might have preferred wizard schools and other magics to be their own power sources or divvied into the existing ones, and wizards as a class could have been allowed to cherry pick powers from multiple Arcane-like sources.
I definitely wanted an independent Necromancy power source, and for that matter a Necromancer, and evocation spells should have fallen under an Elemental power source.
I already have a conversion of the Witch into a Warlock build on the burner, maybe I should make this my hobby and try Sha'ir into another class build.