In rereading my earlier post, I realize the late 1800’s were only clear as to “the best team in baseball” if we limit ourselves to thinking about the league that eventually begat Major League Baseball. Of course, other leagues came and went (the Player’s League, for example) and there was an entire other class of very fine ball players not considered playing over in the Negro League. If we expand our scope to those other groups, then perhaps there has never been a good way to determine the best team.
Additionally, the “World Series” can only ever have in it teams from the US and (one) from Canada. Baseball is played seriously all over the Americas and Asia but those teams aren’t invited to play, so again, “best team” must be limited to “best MLB team.”
With regard to how we can fix this “the Postseason play doesn’t establish the best team” thing (if fixing it is necessary and I’m not sure it is) would be to make the MLB Postseason smaller. That’s never going to happen. But, if we want to just imagine for a minute, what if a simple W-L record wasn’t what determined the divisional leaders. What if some kind of Sabermetricish stat was employed that weighted each win based on the the relative strength of the team it was made against (this stat may already exist but I’m too lazy to Google it). So a win against the Nationals would be worth one but a win against the Rockies would be worth .8 or something. Those scores would need to adjusted constantly because teams play better and worse as the season progresses. The ’13 Dodgers prior to Yasiel Puig joining the team were destined to third or fourth place in the NL West but became white-hot and eventually won the division handily. Beating a late-June Dodgers wouldn’t be as big of a deal as beating an early-August Dodgers. Similarly, different pitchers can make a team harder or easier to beat.
So, there’s lots of factors. But let’s just say that was what determined the top teams and who went on to the Postseason. And let’s similarly suggest only the two best teams in each league played for their pennant. One Divisional Championship Series and one World Series. Just like in the Fifties.
Finally, since we’re really living in a fantasy world, I’d suggest each postseason series be nine games long. Short series are not good determinants in baseball as to who the better team is. One game? Preposterous. Three games? Nope. Five is the minimum, but even then one player’s bad day can sink an entire series and, if the goal of playing the series to find the actual best team, you need to control for that.
Of course, nothing like this will happen. Ever. And that’s fine. It’ll just mean the MLB Postseason remains more like an invitational series that follows the real season.