So if I'm understanding correctly, your argument is this: Teams that have less variation among their primary hitters' OBP will score more runs than we might expect based on their aggregate performance (and vice versa). Is that fair?
Because I tested that and I don't see it.
Firstly, I calculated the residual of a team's actual runs scored compared to the number of runs we would have expected them to score given their team OBP. (obviously other factors affect run scoring, but introducing them would be questions about their correlations with OBP). The Cards scored 36 runs more than their OBP predicts; the Reds 24 runs fewer.
Secondly, I then took the Standard Deviation of OBP, by team, for all batters with 300+ PA with that team. The cards were more or less average, with a SD of .038 compared to the league average of .034. The Reds were off the chart, perhaps historically so, at .063.
So, the question is: Is there a correlation between a team's OBP variation and it's run scoring residual. If yes, it would mean that more (or fewer) variation produces more (or fewer) runs than we would think based on their aggregate performance.
So I then regressed that OBP Standard Deviation against the OBP-Predicted Runs residual. The result? Essentially zero correlation (an R2 .0009). And even removing the Reds, since they're such an outlier, leaves an R2 of .0044.
Here's the full chart.
Now, we could certainly run the SD against a better runs estimator, but I don't think you're going to see the numbers change much. Using OPS as the runs estimator, the R2 skyrockets to a still paltry .0243.
Let me know if I'm doing something I shouldn't here, but unless I really missed something, there's no detectable effect here. We could run it with more data, but I'd be shocked if a significant effect reared it's head. If the Reds, one of the least balanced teams of this generation don't under-perform by much, it seems unlikely to be a real thing.
Ultimately, I agree, team OBPs don't tell the whole story. But if you're looking for the rest of the story, your next stop should be SLG. "Balance", as it were, is likely pretty far down that list.