I suggest you start an Epic WG!
We should gather all Epic OMOP users to divide and conquer the domains! @roger.carlson started some discussions on the Epic UserWeb, I and some others chimed in, but it never gained much momentum.
I already lead the EHR WG and am an active participant in many more WG, so I just don’t have the bandwidth to lead another WG. But if you start an Epic WG, I will help round up the Epic OMOP users and be an active participant. Epic is very complex and requires a lot of deep digging into the source data, utilizing front end experts, clinical informaticians and analyzing what others have done before. My Epic instance is different than your Epic instance, but there are enough similarities for us to compare/contrast our Epics and get us all on a better path. And really, who wants to analyze 20,000+ tables alone?