Instead of "outweigh" to describe the realtionship of Soriano's OBP to OPS, I guess I would go with "mitigate." It's true that OBP is the more important component, but Soriano is currently slugging .525 (after his first AB today) and that's pretty darned good. So, yes, parhaps the OPS is somewhat higher than his actual offensive value--given the low OBP--but it's still pretty decent offensively.
He is a limited player these days. As to defense, just look at the great player in LF for the Brewers--from a defensive standpoint. I'm very skeptical whether Braun, defensively, is any better than Soriano. You put up with it because the guy hits a ton. Soriano does not hit a ton, so it sticks out more.