Here is what I would do if I was gonna try and solo lvl a necro.

Perfect h2h
Perfect parry
Find damage redux
Loot a hero (this is key) :P

After this its just a matter of finding mobs that are either vulnerable to negative and whore out vampiric touch. Prepping your leveling area with touchable mobs will make leveling easier. Disruption is an extremely nice spell for leveling purposes, but using it effectively for leveling will take a little bit exploration on your part. Once you find good aligned mobs/high xp evil mobs that the spell works on you should be able to level fairly easily.