For nightstalker hunter you need to experiment with Max discipline and strength. This lets you do the combo of throwing a poison smoke bomb and then a void grenade. Timed correctly, you can get great kills. I usually run this with a Monte Carlo to keep my strength up since it loads slower than the discipline. As for armor you could try for the helmet that gives you shade step but you can't roll that with disc/str. I usually go with knucklehead radar and the perk that gives you enhanced tracking. It's fun to line up shots before some steps back around the corner after escaping from the smoke wambo combo.