Melting faces just fine at T4 with specific melee build (4p Tal Rasha's + Wand of Woh + Moonlight Ward). T5 still appears to be not efficient to farm, but with a little more CDR and right stats on RoRG, I think I'll start killing things much more faster there.
Actual in-game numbers with EA (which can be changed to storm armor for even more DPS) + MW (deflection rune is awesome!) up:
Damage - 963k (elemental elite should be at 1.6 mil; paragon off. points - 50/50 CDR, 31/50 crit damage)
Toughness - 12.2mil (paragon def. points - 31/50 resist all, 50/50 life regen)