Warlocks have a gazillion rift exotics and no one uses them except maybe Sanguine because of the damage buff which you can do from a safe distance. And now you want people to go drop their rifts, with that long -blam!- animation, in the middle of the room between all those shooting enemies to suspend them? If people aren't using Frostpulse, what makes you think they would use an inferior ability that takes an exotic slot? AND on top of that it's tied to the worst super in the game. You are creatively bankrupt when it comes to Warlocks. Also when was the last time you gave Warlocks a useful PvP exotic?