When I think of dual wielsing great swords, I think of Raubahn and his giant cleavers. Why not make a Berserker dps job based off Raubahn, his and Ilberd's control over the elements of fire and their fighting style being based off of the Warrior job, since Warriors back before the fall of Ala Mhigo did travel around Eoreza as sellswords and an Ala Mhigan could have seen the way they fought and tried to replicate their fighting style, thus the Berserker class is born.

Also, all the attacks of the Berseker could be named after Griffon traits. Like "Griffon's Talon Strike" or Griffon's Buffeting Blitz" or something like that.