I made my Fane a rogue, because he has unlimited lock picks and because he can take himself out more easily with stealth or playing dead. Though in the end it turned more into a Jack of all trades.
Having a undead in team can be quite difficult, because he can't get healed and is vulnerable to fire.
Though if you want to keep him more safe, you could make him an archer, even without Ifans crossbow probably the hardest hiting class in the game.