I've been doing 2 person smite runs with my partner in game.
Mo/W and E/Me.
The monk tanks while the ele nukes. We use roughly the same build (dependent on protective bond) but use some different skills. The major factor here is that although fire doesn't do much, burning will. Keeping incendiary chains, searing heat and immolate on the aatxes will kill them quickly.
As the ele, I've been both air and fire. I can tell you that fire kills things much quicker than air. Undeniably, air is much more useful with blinding flash and enervating charge.
The only problem with this, as with other builds using only mages, is that the grasping darknesses give us a little more trouble than we normally have. Originally we also did ele tank and prot monk healer, using distortion to prevent interrupts during cast. This was bad because we depended on the ele to deal damage and the squids sucked all energy. It ended as a slow staff firing to the death.
On the other hand, we've done 2 person smite runs (albeit much much slower) with W/Mo and Mo/E. The aatxes took long to kill (but bleeding them back eventually did it) but the squids weren't a problem at all. And the smites are fine as long as you switch targets when you see them cast shield of judgement. The monk should also attack them with wand/staff to clear away reversal so the warrior can land major hits.
Overall, I think 2 person smite runs are a great idea...more people should give it a try rather than sitting in temple waiting for a full party. Of course this way, you'd have to be prepared and coordinated. I think this is also true for fissure, although I believe you'd need more than 2 because of the monks. I've been in a fissure party of 4 that had made it to the forge (and completed all the quests to activate the crafting). The other 4 people dropped out around the tower quest with the first eternal.
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