A Ghoul faction would be cool. But a legitimate army, not just another Underworld or Necropolis.
Aye, and they'd have a nice, prosperuous town aswell, which is also not anything like Underworld or Necropolis. They would not be the refuges and underdogs to men, it would almost be the other way around. With almost, I mean they wouldn't shoot humans on sight or anything, they just don't want to be involved with their business, unless it pays well and they are treated with respect. They are also good caravan customers.