Mages also don't have heals, cures or duffs which is all a BP has going for them. It completely depends who you attach. A priest can deal shit damage to an unduffed 1450def warrior yet a mage will do a lot more damage because it's based on resists. Same thing goes if a rogue with MS has 130 to all resists then the mage will deal less damage than helis.
Point being, mages damage is much less random than a typical melee class, which is why mages pwn... hardly anyone carries around fire talia.. and few carry around other resist talias in normal pk. (although they should)
Back to the topic, as light I did average 500-550dmg with imir +1/rom and elixer +8.. as fire I did around 600-700.. both being 160int and rest into MP.