After playing all the tanks a fair bit, I noticed that Warriors felt the worst when running wall to wall in dungeons. I suggest a simple reshuffling and renaming of a few abilities that would make the job not only feel a bit more streamlined but just make more sense.
Step 1: Rename Mythril Tempest to Steel Cyclone, rename Steel Cyclone to Mythril Tempest
Step 2: Change AOE combo to Steel Cyclone > Mythril Tempest. Steel to Mythril is a common progression in FF games throughout the series.
Steel Cyclone
Lv. 10 Weaponskill
Range: 0
Radius: 5y
Delivers an attack with a potency of 130 to all nearby enemies
Mythril Tempest
Lv. 40 Weaponskill
Range: 0
Radius: 5y
Delivers an attack with a potency of 100 to all nearby enemies.
Combo Action: Steel Cyclone
Combo Potency: 200
Combo Bonus: Extends Storm's Eye duration by 30s to a maximum of 60s
Combo Bonus: Increases Beast Gauge by 20
As it stands, Warrior AOE combo is at a distinct disadvantage from the other 3 tanks as their first weaponskill in the combo requires both A) a target and B) is only a cone. This shift of abilities brings all tanks to the same level.
Step 3: Replace the old Steel Cyclone with Overpower, and restore it's original animation.
Overpower
Lv. 45 Weaponskill
Range: 8y
Radius: 8y (cone)
Delivers an attack with a potency of 220 to all enemies in a cone before you.
Beast Gauge Cost: 50
Step 4: Replace Steel Cyclone Mastery with Overpower Mastery
Upgrades Overpower to Decimate.
With these 4 steps, you have a more streamlined AoE combo for warriors that focuses on spinning their axe around them from an aesthetics standpoint. You also have a Beast Gauge combo that upgrades from a cone to a 360 aoe as well. It makes Overpower's cone much less likely to miss as you typically have everything gathered before generating the beast gauge to use it, and in terms of feeling like a visual upgrade, Overpower and Decimate both involve smashing your axe into the ground.