Black orc is one of the best pve tanks I have ever played. Although the dorf tank is the best at pvp due to incredibly powerful knockbacks and knockdowns (orcies only have one or two depending on spec and not that powerful). The chosen auras are incredibly underpowered at the moment actually but its still beta so that will change im sure. I will say though the greenskin beginning quests are freaking hilarious and very very cool looking in some cases.
As far as looks nothing beats a decked out chosen, even in lvl 11 pvp gear they look meaner than a menopausal nun.