Too bad he doesn't have deluge. My theory is that it's not only the type of weapons that determines the damage, but the number of weapons one has. In other words, throwing down more of them, the more that you have.
My first brute Stsin has a lot of weapons and her deluge can be sick:
As for a brute with a lot of weapons, Stsin VI may be hard to beat:
At level 32:
At level 107:
She may not look it, but she's a brawler. Hardly uses weapons anyways.