Run differential is one estimator, but runs scored/allowed are subject to the whims of chance, also known as sequencing (or, luck). By this calculation we have four more wins than we "should" have. An even more granular (some might even say precise) version of estimating wins & loses is BaseRuns, which takes the weighted run value of every single outcome that occurs & projects runs scored/allowed from there (in an attempt to eliminate the whims of chance somewhat). By this calculation we have played to our exact current record. Keep looking to cherry pick stats. At this point the Brewers are what they are. This team is average at best.