I my unpopular opinion, Gunslinger is great for PvE in addition to PvP. Use a Hand Cannon or a Scout Rifle and chain precision hit. Use knife juggler for adds.
From best to worst (in my opinion, I could be wrong):
PVE: Nightstalker, Bladedancer, Gunslinger
PvP: Gunslinger, Nightstalker, Bladedancer
Note that Bladedancer invisibility is VERY handy during the first part of Crota raid
I have maimed Nightstalker since it came out, but switched to gunslinger recently. Trip mines are so good at killing people camping in corners, I've gotten so used to the throwing knife that I try and arc my other melee attacks now.
I mained gunslinger and still love it but I'm partial to nightstalker. I've been using my bladedancer more though but I keep feeling like the super isn't powerful enough anymore
The arc blade takes two hits on some ads and majors takepretty much the whole thing