Looking at which television markets have teams and not, and assuming the following:
- The NFL wants two teams in LA.
- For a variety of historical and political reasons, Green Bay and New Orleans aren't going anywhere despite the small sizes of their markets.
- The relatively large markets of Columbus and Orlando are covered by Cincinnati and Cleveland, and Tampa and Jacksonville, respectively, and don't need teams. Similarly Sacramento, Milwaukee, and Hartford/New Haven are close enough to teams, not to move one there.
Then one of Oakland or Buffalo should be moved to LA, and the other should be moved to Portland or St. Louis.
St. Louis is a bit larger television market, but Portland is growing much faster and will probably become the larger market sometime in the next decade.
If the NFL does that, then 33 of the largest 35 tv markets will be covered, leaving only St Louis/Portland and Salt Lake City.