If I were to redesign Warrior I'd build it from the ground up around Inner Release. You're playing a berserker, the whole point is to go berserk. Also it looks cool having the red glowy eyes.
First off we get rid of all the mitigations, we won't need them. Instead of building up beast gauge to do Fell Cleave you build up beast gauge to proc Inner Release, at which point you go berserk and gain +20% damage mitigation and +20% damage output for 30 seconds. This changes your regular combos to new fancy moves that do basically the same thing but with a new coat of paint to really sell that you're giving in to your inner beast and attacking with reckless abandon. What Inner Release also does is that for every 5% of health you lose, you gain 2% increased damage and 2% increased mitigation, so the more damage you take the harder you fight, and the more difficult it gets to kill you. This is why we won't need any of the other mitigations, it's all baked into Inner Release.
For every combo you do you get a free Fell Cleave/Decimate, which still auto crit, and once you run out of Inner Release you smash that Equilibrium to bring your health back up, ready to repeat the process. It'll essentially be 30 seconds of unga bunga followed by 30 seconds of building up more gauge to do more unga bunga. This puts warrior in a space where they rely on vit, crit, and tenacity as their main stats and gives them a risk/reward dynamic where you are encouraged to take damage to increase damage while still keeping the burst damage nature of the class. I have no idea what to do with the oGCDs for this, but I think at least Shake It Off should be kept as the one mitigation skill warrior has.
No clue if this is even a good idea, just a thought I had.