Having just gotten Action PC Baseball, I have, once I get the hang of the more complicated mechanics, the means to bring two of my longstanding fictional baseball teams to life.
Connecticut Corsairs
The Corsairs (named for the F4U) are the archetypical “billionaire’s toy”, with a classic degree of “bought talent”, especially pitchers, since in-universe they pioneered the now-standard “many pitchers throwing all-out”. They’ve won several World Series and consistently do well. I’d stuff the Corsairs full of good players.
New York Owls
The New York Owls are the opposite. They are the baseball equivalent of the Sterling-era Clippers, existing purely to leech off big-market revenues. In only one season have they not finished last. I’d stuff the Owls full of bad players. Really bad players.