I wouldn't play a tank where enmity was the only outcome of my abilities. I'd feel I have to be doing something to bring the boss' HP down.

However, I would love to see a world where tanks were required to have "tank mode" on when holding the boss, and had tank stats which actually mattered - for instance, Parry (affecting both parry and, if applicable, block rates), Evasion (what says on the tin) and Resistance (overall damage reduction and healing received increase). These stats would only be effective when in a tanking stance.

This is the first MMO I've played where the tanks are encouraged not to be in a tank stance in order to do more damage. Bosses with higher sustained damage and lower DPS checks would, in my opinion, be much more interesting than the current meta in which tanks are essentially a DPS class with extra cooldowns. To put in perspective, I've moved from a world where tanks would output approximately 1,000-1,500 DPS on a boss fight, DPS would do around 3,500-4,500. This meant that everyone's role was far better delineated than in FFXIV. Tank DPS was a nice to have, but was not vital to success beyond a point, more important was to be able to survive sustained outgoing damage from the boss.