PA
I understand why you'd think the way you do. Baseball has the least amount of imagination especially when compared to the NFL and NBA. The only significant rules changes in the last 100 years were tinkering with the height of the mound and the margins of the strike zone. They did invent the Looguy which is a stain on the human race that Manfred is thankfully trying to kill.
You are absolutely correct about boring. In the places I named they all have had long stretches of being uncompetitive due to budgetary constraints. Losing and bad baseball is the worst kind of boring. It is hard to envision how they could be worse with cities of at least 2 Million people that are some of the richest in the world.
As for Free agents - I am not sure that Latin players would consider Asia any better or worse than the US. Player agents may even steer players there in the hopes they become Stephan Marbury. Surely a team in Tokyo would have more than a 70MM salary budget some of these teams have. Would somebody take 30/40 million less plus potentially big endorsements to play in Philadelphia vs. Shanghai? Have to think some of them might take the plunge. I can see a bunch of very good players might make a million or two more in Asia taking the money rather than staying in the US.
Imagine how interesting the Yanks or Dodgers landing in Tokyo to play the World Series would be. If you can't then you might be a baseball fan. Baseball should be a global sport controlled by MLB.
FWIW if I owned a team I'd want the Billions that would be available in Asia's best cities vs. the 10's of millions available in 2nd tier US cities.