There is actually a relatively short list of things which are actually mandatory for tanks. You should be able to meet the mitigation requirements of any fight. You should be able to provide equivalent dps, accounting for differences between burst damage and sustained damage, as well as raid buffs (the last of which I'm against tanks having). You should have a toolkit which allows you to obtain snap enmity.
Outside of this, it comes down to the total picture. How does it trade off? For example, WAR has much cheaper enmity generation than any other tank. That might be fine, if another tank can make up dps in another area. Perhaps they use a mobility advantage to squeeze in an extra GCD to make up for it.
If you look back to ARR, we didn't need all that much to actually tank. The problem with terms like "Utility" is that it becomes a wastebasket term for any ability that we want copied over from another job. Plunge is utility. WAR needs a Plunge clone. Divine Veil is utility. WAR needs a Veil clone. Cover is utility. WAR needs a Cover clone. There's no point in hoarding all this stuff.
If you give tanks all their own unique chances to shine, the balance will fall out of it. Your approach only works if you are truly, and completely committed to homogenising all the jobs. To the point where none of them have any identity left. But even that's better than the partial homogenisation that we presently see that only benefits WAR.
Yes.
So as I was saying, that heretic was fighting like a man possessed. Even after he took several wounds, he showed no sign of pain─though there was no mistaking the blood. As the fight wore on, it began to soak through his armor, spreading to every ilm of his body. But when it began to rise and envelop him as a mist, I realized it wasn't blood, but something dark and twisted...
One of the very first in-game lore descriptions of DRK is that of a knight who fights beyond pain, beyond mortal wounds, in order to administer justice. WAR is just Defiance. DRK is Grit.