There is ONE way to do decent damage with a brawler. Be a Bugbear, and go Shock Trooper for your paragon path. With large-sized spiked gauntlets that receive a size-boost to their dice for being off-hand, you're punching d10s.

But, in the end, Brawler seems to be about EXTREME lockdown. On one guy at a time. But that one guy is going nowhere.