For example, there are other leagues in the world with playoffs after the regular season; Liga MX from Mexico is a prominent country/league to use them. But, end of the year playoffs to determine a champion is unusual and goes against the grain of the traditional leagues. The English Premier League is typically the league of choice when it comes to FIFA expectations for how soccer should be represented to the world. MLS has made a conscious choice to go its own way on the 'playoff' variable and has aligned itself with its neighbor, Mexico.
The argument against playoffs is to say that regular season play has diminished value, which may be true. However, with a runaway first place team in a traditional league without playoffs, the end of the season becomes anti-climactic. Arguably, MLS playoffs are the best reasons to watch the league. They are exciting with controversy at times and are less forgettable than regular season games.
MLS has driven the administration of its league according to what works. The single-entity philosophy, in which owners are working together running their teams to see the league succeed as a whole over any individual team, has functioned well enough over the years to provide opportunities for continued growth of the league. Also, for operational purposes, MLS has decided how 'designated players' (usually star players from other leagues around the world) are signed by teams with specific allotments and how many slots can be filled.
While some people would argue that single-entity is un-American in its ideals, more common to socialism than capitalism, it can also be viewed as analogous to regulation of the stock markets. The league is following American ideals in everything it can control and single-entity has been the agreed system for how to keep a steady return on investment without too much risk involved.
Another big soccer issue that MLS has yet attached itself to has the smell of going rogue. So far, there has been a refusal to do as the other famous leagues do when it comes to promotion/relegation. It's a dead concept as far as MLS is concerned.
MLS believes it is bound to the rules of the sport on the field as governed by FIFA, but anything outside of the field is up for interpretation. This is how MLS has decided to go way past the FIFA recommendation for 20 teams in a given league. The EPL and other famous leagues may have 20 teams, but there is no formal declaration by FIFA for how many teams should make up a league.
The announcements this week for expansion did not exclude for even more of it down the road. The league says it will go up to at least 28 teams. And, this leads many to believe that the league may exceed 30 teams at some point in the near future.
What's next on the MLS americanization agenda, more than the standard 38 regular season games? Anything ambiguous is fair game. I think water breaks will become more of a standard, as it has been used in the past for MLS games. Possibly, the water breaks may eventually be used as a timeout for television to take commercial breaks. Also, the amount of substitutions allowed has become a cause for many, including the famous coach Pep Guardiola of Manchester City. We might see changes for how substitutes are used in the future of the MLS game. We know for sure that MLS has volunteered for Video Assistant Replay (VAR) and wants it to be part of its league. This is a coming reality.
For a league not able to write its own rules, MLS continues to espouse its independence through any means necessary. When it doesn't need FIFA's permission, it doesn't ask for it. It wants to do things its way as much as it can. Forty teams in the league could be the final answer for the Americanizing expansion of soccer.