Where's the AoE? Cluster Bomb is too slow and Pistol Whip needs to be in melee range. Ele and necro are far better for AoE.
Cluster bomb and dagger storm and two of the best aoes in the game.
Yes cluster bomb is too slow at range and if you run to the front of a group of enemies and spam cluster bomb then you're gonna die in 2 seconds. You're not meant to hang back throwing down aoes like an ele, necro or engi. Cluster bomb is best used at point blank range and thieves have enough teleports and stealth skills to make it work.