Oh, the spell deletion. I think/hope this feature is in Skyrim.
Do you?
I think it will function like this.
Let's take fire as an example. You'll have two or three types.
Ranged single and multi. (Don't think multi would work without auto aim though, and we don't want that, do we?)
Enviromental.
You'll increase the use of them as you progress through the skill tree.
That's my guess anyway.