I haden't even considered the old gods stuff, to be honest.
Really the more variety the better
Looks like you don't need the glyph to be a necromancer after all. Stop necro your own topic.
Well like I mention before, Lore wise Necromancy is or was part of the warlocks arsenal making it a half bake class if it was on its own, that is of course until the Lich King appear and took it to a whole new level. Its seems to me that instead of a Glyph or being part of Affliction (which would makes sense) this could also become a *Specialization*(HAHAHA this would make soooo many people specially DKs very mad if they did this, BUT lore wise it makes perfect sense). I mean just because Warlocks no longer use necromancy doesn't mean they DONT know it. To Warlocks (if you fallow the lore) this dark knowledge must be the basics of their craft since by the time Warlocks resurfaced it was in a Hero Class in Warcraft 3.
Blizzard haven't explain yet clearly the source of power of Necromancy but my guess it has to come from the *Shadow*, they do hint it when they say that the Forsaken worship it. But WE warlocks COMMAND it , just as DEMONS command sometimes undead, and we CAN command dose demons if were powerful enough, so the idea has merit. Specially if its accurately lore wise AND also remember *Traditional* Necromancers mechanics that Blizzard where working on they DID say felt more like Warlocks than a Hero Class that's why they scratch it and gave it all to DKs. Sadly if haven't noticed the same thing is happening with the Demon Hunter, his skills are being given to the US the Warlocks if this keeps up soon we will have stealth, using his war blades and our chest with tattoos or even BETTER we can turn or buff a PLAYER with our current Demon so he gets benefits from it like turning them in to demon hunters hahahaha that be fun and people would beg us to Join their team so we buff the tank or healer! Or if Blizzard is lazy this might become a Spec they created a lot of controversy the the Glyph *Demon Hunter* already so WHY not Necromancy, right?
My suggestion if they ever do any Hero Class Demon Hunter or Necromancer etc. they should expand the Lore and make a new class call *Slayer*,*Sentinel*or something similar and THEN add the spec, like Demon Hunter, (Demons and Elementals) Shadow Hunter (this could cover the Loa, Undead spirits all together), and Warden (hunting and guarding prisoners). This would then make Perfect Sense lore wise and this idea could be more developed, old hero classes need to evolve. Oppps got side tract again. :S
Anyway coming back to subject, any Idea that add more uniqueness, customization, mechanics, fun factor or DROOL factor to a Class and its lore wise we should totally supported . Hope Blizzard listen and add them after they finish polishing MoP.