If they started MLB from scratch today most of the small-market Central time zone teams simply wouldn't have baseball,and Chicago probably shouldn't have two teams. At the same time, none of the last four expansion teams which theoretically went into Southern and Western population centers have proved more successful or wealthy than the Reds or Twins etc.
If they expand and realign and go back to four divisions having the playoffs just be conference record like the NBA, or at least all wild cards after the top two teams, could work.
It an also be somewhat cyclical, though maybe not trending that way in current financial reality.