Some idears:
People seem to have their opinions about the template but I have a throwing Sampire that also dips into wraith form when necessary (spirit speak stoned over). I can solo a bunch of stuff in the game (mini-champs, named bosses, a few peerless), probably could do most of it if I was better at UO. I also have a swords sampire, and he can chew through spawn. But both of these temps rely heavily on the suit and weapon. Millions of gold. But then, these two can make are my PvM money-makers.
I have a necro/mystic/mage that didn't cost nearly as much to outfit and there are plenty of times he's the only option. The ability to cast a RC, use Stone Form, cross heal, might make PvM more of a group thing for you and your girlfriend, whereas on a Sampire it's basically Lightning Strike, Lightning Strike, Armor Ignore ftw. And for a while the only new creatures they were pumping out had this nasty damage reflection that made anything but joust-and-heal melee impossible. It broke the efficiency of the Sampire, because it made the healing pointless.
Since you already have a tamer in the group, the role of Sampire or "tank" might already be filled by a dragon or something.