Ah, the homogenization card. I knew it had to show its ugly, idea-silencing face somewhere.
The stances would still be very different in what they do. PLD's stances alter the way you generate gauge and its DPS stance does something completely different from that of the other two tanks. Grit/Gritless locks two different abilities with opposing effects and alters your mana generation. And WAR's stances are vastly polarized and provide completely different abilities and buffs to your damage and mitigation.
The stances are VASTLY heterogenous in how they do what they do, and what abilities/mechanics are gated behind them. Their ease of use is apparently the sole needed metric that you have for homogenization and I submit that that is a fallacious and wholly incomplete (and frankly, a little uncreative) view of a larger picture.
For your statement to hold water, xOath/Grit/Defiance-Deliverance effects would be as follows:
Shield Oath: reduces damage taken/dealt by 20% and increases enmity.
Defiance: reduces damage taken/dealt by 20% and increases enmity.
Grit: reduces damage taken/dealt by 20% and increases enmity.
Sword Oath: increases damage dealt by 5% while adding a 75 potency to each auto attack.
Deliverance: increases damage dealt by 5% while adding a 75 potency to each auto attack.
Gritless (now a stance): increases damage dealt by 5% while adding a 75 potency to each auto attack.
PLD: AAs/blocks/Holy Spirit generate gauge regardless of stance.
WAR: All beast gauge abilities usable regardless of stance.
DRK: BW/BP usable regardless of stance, Syphon Strike MP regeneration and Souleater self-heal identical regardless of stance.
Now ^that's^ homogenization.
