Good first char to get 50+ with?

[soup]

As far as the topic at hand, I'd say shaman or necro.

If he's new, he's going to want to be able to do shit on his own and not rely on others 100% of the time. I didn't include mage because they seem kinda boring to me. Send pet, cast a nuke or two, ok you're done, but I suppose that's personal preference and mage is certainly worth considering.

The only problem with shaman is it doesn't have as much instant gratification. You don't become a powerhouse until 34+, whereas the necro is beastmode pretty much starting at level 1.