what about MO?
I'd add a step: between switching both bosses go and AoE hunt the mobs in the library where you killed volfid. They respawn every 2 Minutes and you can leave more time for Firetraps and Lighnings to spawn. But for real EXP I'd spam Hazardous Valley over and overQuote:
I'll add another Hint
If you had spawned G'ni of fire, it takes 3-5 mins to summon many fire traps for a good leach of xp, while waiting for summons, go to the room of lightning, kill the gate to summon the boss, he will also summon lightning minions 3-5mins, go back again to g'ni by this time he had summons many fire traps, kill most of it, then go back to lighting kill again the minions
so going back and fort between those 2 bosses will leach the best exp
and uh! make sure that you don't hit the 2 bosses so that they can summon unlimited for the 2 1/2 duration of dungeons, you can move around the area, maybe farther away from them, don't use yet Big Skill AOE, just the normal AOE skills to gain exp