I don't know why you need Dark Drinker with a sniper and pulse rifle. That sounds like personal preference, nothing to do with the subclass. -For PvP use the Voidwall or Vortex grenade. Triple Jump. Black Hole for super. Envenom for smoke. I always run with high armor and high agility with very low recovery. Use Lockdown to extend the duration of smoke and grenades and for the last spot use Keen Scout since you already have Shadestep from Graviton. -For PvE I prefer Voidwall. Triple Jump. Black Hole or Blood Bound and Vanish in Smoke. If you're with a team use Courage of the Pack or Light of the Pack with your super to create orbs or boost armor and recovery. Also I select Shadestep and put on Skyburners Annex helmet as it has support perks and is better suited for PvE. -For armor I use a perfect balance for Intellect, Discipline, and Strength. I find that all Nightstalker abilities are very useful so I don't prioritize. If I were to prioritize in PvP I would put more emphasis on Dis and Str since you can throw more smoke and grenade combos. Also if you have Ace of Spades from the gunsmith that is a great PvE hand cannon. Not always the best option but still worth getting.