Tanks should absolutely not have actions that spend enmity in exchange for increased damage. The rest of us have no enmity management actions anymore. Even back when we did have enmity management actions, I could use Diversion and Dreaming on cooldown and still steal aggro five minutes into a raid/trial. I shouldn't have to play my job worse in order to avoid getting killed, and that's what I'll have to do if tanks get actions to spend their enmity in exchange for more damage.