Well, if you're gonna tackle +4+8, you're gonna need some toughness. I never thought of myself as a high-DPS, but I only have 2 tricked out incarnates, one MM and one claws scrapper. The MM can take out a pylon at a decent pace. The scrapper cannot, even though I built, including incarnate, for damage. Ironically she can tank 5 monsters on monster island in PI, even though not built for toughness. I think there's an imbalance there somewhere.
P.S. I don't claim to have some well-designed DPS build, just that I took the DPS stuff in incarnate and most damages are in the 130% range.