OPS does not measure everything in baseball, but it does measure a lot. As part of my Petco Park analysis I needed to quantify the relationship of a team's "net" OPS (OPS Hitting - OPS Allowed) for a season help quantify how many wins the differences in homefield advantage (measured in OPS) is worth. This is pretty easy: gather the net OPS for teams and compare it against their winning percentage. The chart below summarizes this:

Not a perfect fit (r-squared is .82), but very strong, a good enough to estimate impact in changes in OPS caused by a ballpark over the course of a season.