Playing multiple games i realize that taunt has always been under utilized and never useful outside pve scenarios. I feel like this game (tank builds) in particular could benefit from a taunt that acted as a self buff and a enemy debuff. The effect wouldn't even need to work on pve bosses as its taunt function would remain unchanged.
If i may suggest, add a cost reduction to the taunt effect when targeting taunted targets or make taunt increase ability costs on taunted targets when they attack somone other than the one who taunted them? I feel like this could add a bit of more use for taunting outside dungeons or bosses.