I don't quite see how the tanks are the same. They certainly have similar functions: an enmity combo, a utility combo, a damage stance, a tank stance, a stun, group enmity, group area enmity, and then a couple unique buffs for their job. Any tank you make for this game is going to need those basic tools. If its aesthetics, that's your own thing. For me, it makes sense though for the person in heavy armor to be more survivable than the person wearing a bikini.

@duelle
That is an interesting tank idea and I'd like to see it implemented in ffxiv. The biggest concern is that the delayed damage tanks may eat in to healer dps times, which makes it a huge detriment to endgame groups and thereby unpopular in the meta. There's probably a few tricks and testing to find the best ratio of damage:delayed-damage, but it is something to be aware of when developing the idea.