We know MLS will be expanding to 30 within the next few years...I suppose that's assuming all the finances are still on track after COVID.

Austin FC will begin this coming season. Charlotte, Sacramento, and St. Louis will be the next to come on board.

There has apparently remained an open channel with other cities though. Las Vegas, San Diego, Indianapolis, Detroit, and Phoenix are all in the hunt according to SBJ.

Now, the next logical number is 32, but let me propose for a moment that MLS may have 40 as their ideal number.

You can divide MLS into 2 leagues at that point. If you have 20 teams in each league then they can play the traditional double round robin. That's 38 games and then perhaps you can create a playoff system that pits squads from either league against each other. Of course, 36 could be a reasonable number as well. You could divide into 2 separate 18 team leagues and still play the double round robin. Germany and some other quality leagues have 18 as it is. That would be 34 games before playoffs begin.