Aren't necromancers (such as the Sload) well known for plagues? That sounds like the world of destruction/restoration (remember that restoration has some of its own nasty magic in it, as well) to me.
Well, they've been associated with that, but I don't think they're manipulating germs with magic to make a plague. There's likely enough plague going around with the filth and rotting bodies. As for the Sload, they're far too typecast as a race of necromancers. They're the only sentient life form on that island, so they're just raising their friends and pets from the dead. Plague usually devastates in places where people aren't accustomed to the livestock causing the problem, so the separation of the island probably had a lot to do with it.
Conjuration seems to go with dealing with souls and minions, but perhaps that spawns from an ignorance on necromancy (considering we only have one real book source).
In some ways, but I'd want the Daedric skill to only concern itself with the daedra. I don't think undead should be summoned exactly from somewhere. You should be able to raise a zombie in fifteen game minutes perhaps with a ritual, and a skeleton warrior in an hour or two depending on how well you can put them together. Then with mark/call you teleport them to you to fight. They should probably give you a lab assistant in the game to build you some.
Restoration would also deal with creating the magical bonds that allow the body to move about, unless that involves some sort of odd alteration-like powers.
I'd probably go with the alteration explanation before restoration, I'd assume restoration just deals with living bodies. My theory on the necromancy would be that since it is about the manipulation of souls, making an undead servant is like enchanting the body by ritual intelligence based magic with a soul to perform the motor functions of the body, without applying their cognizant functions. So, you take the soul of the rat and put it into a bear, it's not familiar enough with the motor functions and wouldn't operate as efficiently.
I've wondered though, what is the Enchant skill if it isn't Necromancy? If you can apply a soul to a sword to make it cast fireballs, how different is it to apply that same soul to enchant a body to resume operation? I'd say for the difference enchanters shouldn't be able to use people souls, and they can only make on strike/on use/and permanent enchantments, and they can't employ soulgems. They have to apply the soul right when they get it.
To that end, enchantments should be stackable to a degree, but only the stronger ones are able to be made permanent. I'm sure they would have many balance issues with that, but enchantments in general need many more everyday uses. You should even be able to enchant your weapon with your mana pool, so it drains your mana pool on strike.
And saying necromancy is a school of magic is really a moot point. As I already mentioned, they're purely academic. The only reason necromancy ISN'T a school is because of Traven's disgusting policies and the devs not wanting to take the time to implement it.
Sure. It makes it easy to talk about this way though.
Mysticism, I suspect, would be the primary school of the Necromancers if they went by schools.
The cult of Necromancy split off from the Psijiic order, not the Mage's Guild. The Old Ways encompassed all magic but especially Mysticism which is still the most obscure and least understood sub classification of magic on Tamriel.
Like Shades said, the primary craft of Necromancy would appear to be bending souls to one's will. Sometimes these souls take on corporeal forms like skeletons or flesh revenants but very often they don't. Binding ghosts, wraiths and other apparitions to one's will seems to be common for Necromancers. In the games, perhaps for the sake of simplification, this is classified under the Conjuration school, but since these souls would come from the Aethur and not from Oblivion I'm going to go out on a limb here and suggest the process of summoning them to do one's bidding is a different although superficially related process from summoning a Scamp or Atronach from Oblivion.
Simply trapping the souls of humanoids for later use is probably much easier and more convenient, and the God Of Worms found a way around Arkay's laws to make that much simpler for his acolytes. Just because we don't actually see Black Soul Gems before Oblivion doesn't mean there was never any such thing or that there weren't other ways to take mortal souls. I suspect that the apotheosis of the God Of Worms made the act much more wide spread, though, and the death of the Altmer calling himself Mannimarco during the latter days of the Third Era probably didn't do much in the way of stopping that Worm God in the sky from placing this power into gems.
That sounds pretty good, except for getting the souls from Atherius. I think their defiance of Arkay is in their prevention of letting the souls get to wherever. The dreamsleeve scrubs them clean anyway, enchantments and necromancy are ways of applying that soul's energy before it returns to the scrubber. Necromancers are going green as the first mystical recyclers.