Personally I see that all 3 have merit, but as I'm less of a sniper, or a straight-into-the-melee guy, I prefer the Warlock most. Though I am most looking forward to the new sub-classes for both the other classes. This could be due to me having issues letting go of Voidwalker as a Warlock, whereas I have no massive affinity for my Gunslinger or Striker, so Nightstalker and the Thor Titan class (can't remember the name) so I am keen to try those out.