It terms of straight PvE damage, void walker. With obsidian mind helm. For PvE support, sunsinger, you can use two grenades, have friend's talents recharge quicker and if all goes to hell, revive... And I usually always run sunsinger for nightfall and hard raid. For PvP I prefer void walker with voidfang vestments to always have grenades, and because the super is actually useful in clutch moments.