I like the following:
1961 (first year of AL expansion)
1962 (first year of NL expansion)
1969 (first year of divisional play, four new franchises)
1975 (Astros were terrible that year so it's a good starting point for a challenge, plus the following winter is the last without free agency)
1976 (first full ensuing winter with free agency)
1977 (Seattle and Toronto enter)
1980 (full decade of my youth)
1993 (Rockies and Marlins enter)
1994 (first three-division year)
1998 (Rays, Diamondbacks enter)
2013 (Astros to AL while at rock bottom and first year of 5 teams in every division)
I have a current solo league that started in 1971 because it was the year I was born. I let the AI sim those games and I watch with daily RTS. I'm also actually playing out every game in an Astros solo league that started in 2013. I switch back and forth, depending on whether my wife is watching a show that I ghost-binge watch with her.
