In the form of a deep-dive journalist's expose', health care leaders Richard Gilfillan and Don Berwick publish a two-part series in Health Affairs about what drives the profitability and expansion of Medicare Advantage. Authors also focus on the new and different dynamics of Direct Contracting, which they view skeptically as well. (Direct Contracting would essentially simply replace MACs in defined geographic regions. For example, Novitas might have Texas, but Direct Contractor X could take over all Medicare claims for Houston.)
Berwick also had a good article in January 2020 on "Medicare for All" - policy ins and outs. Here.
Cross reference: NYU's new Master's program in law and healthcare business strategy.