The issue with stances has always been a few things.
1.) If you take the stance route of Vanilla where spells are locked, you get a cumbersome system with no benefits.
2.) A X% stance turns into simply aura swapping or camping in a specific stance. In MoP Bererker Stance was useful like one fight? Every other choice was Battle or Defensive.
You either get this weird system that has the illusion of benefits or you get a system that hamstrings the Warrior.
Flavor is something the class could use more of, but stances are not the answer. Visual effects, or taking the route of the Diablo 4 Barbarian with multiple weapons, is a much better way to add some flavor to the class.