Well if you want to shift the Rays into the NL, does this alignment make sense:
NL East: Expos/Nats, Phillies, Braves, Marlins
NL Central: Rays, Cardinals, Cubs, Pirates
NL West: Reds, Dodgers, Astros, Diamondbacks
AL East: Yankees, Red Sox, Blue Jays, Tigers
AL Central: Indians, Twins, Royals, White Sox
AL West: Mariners, Athletics, Angels, Rangers
Alternatives: Shift a team from the AL Central into NL Central.