I think if we really want to improve Berserker, we need more than just one primal burst. Berserker should have access to more burst. I think if the warrior has access to F1, F2 and even F3. Then Berserker will be more viable in pvp as well as more fun to play.
Let’s take Hammer for example.
F1: Earth Shaker: Aoe 2s stun.
F2: Rupturing Smash: Aoe pull.
F3: Flying Thor: Toss hammer at enemies for knockdown (up to 3 enemies will get knockdown). When press again, the warrior will leap toward the enemies for another knockdown.
And with other weapons set, you can add defensive burst abilities to help warriors stay alive so warriors won’t need to rely on stances so much.