My opinion is... its really, really close, but not QUITE there. The problem with War is its skillcap/effort put into its dps rotation is disgustingly high compared to the other two (and very easily screwed over by mechanics), and for this reason along with lack of utility, they should ideally be the highest dps of the 3 (not by much, but by like ~200-300 dps). Drk needs a bit more damage to be a little closer to War (they bring slight utility and their damage is significantly easier to apply in raid settings) and Pld should sit on the lower end as its utility is highest (again, not by much).

Alternatively, give all 3 tanks some unique utility buffs (like Pld mitigation for Passage of Arms, War gives group HP/healing, Drk gives group shielding) and put all the tanks' damage/skillcaps in a similar spot. Which would probably result in tanking being a bit more boring due to war skillcap lowered rather than pld/drk skillcap raised.