I've found the best xp/hr in scholo is in the first few rooms, where you can gather up a shit-ton of mobs and aoe them down. If you take your time and loot for cash, you can spend 15 minutes doing that, and repeat. clearing the whole instance isn't as efficient, and the boss loot is pretty pointless (though I did get a decent healing totem).

It's nice not having to drag the slaves through a huge city, and realize they're all dead to some random pop while you're off aoeing down zombies.