When I first played and my options were gun slinger and blade dancer. I chose blade for PvP hands down. Gunslinger was more useful in pve. Nightstalker came and like you I used that in PvP and pve and never looked back. Invisibility and shade step and a bow an arrow you can't go wrong. But recently gunslinger is making a come back with me and found using it more in both modes. Blade however there isn't a lot of use when comes to super since its melee based and get close to the boss they just step on you. I use it now when the bounty calls for it then I'm done.