As for being capable tanks it's not like we need that much, I think changing Pressing Attacks target legacy to "Aoe Skill targets" and make it affect Threatening Shout, Routing Cry and Pressing Attack will be enough to get us the AoE aggro we need.
I agree that a legacy or trait to further boost aoe skill targets for forced taunts would help a lot. That really is the only major flaw I can see in cappy tanking now, as our survivability has increased a lot. That said, I wouldn't want to lose the Pressing Attacks target legacy, as I do use that and know many other Captains who do too. The trait that gives +3 targets for Threatening Shout should give +5 at least.