I have made a revision to the ballpark rule that will add an interesting wrinkle to the future of the league and could impact which park you choose in the draft:
Owners will pick their ballpark at any time during the initial draft. every 1964 major league ballpark will be available, 8 AL parks and 8 NL parks will be selected, team names must start with location of the team, AL/NL alignment, divisions will be based on geography. When your selected ballpark falls out of actual use, you can move on to the new park (and/or city) that the real-life team in your park moved to, or you can choose to keep your original park. If you keep your original ballpark, you must remain there for the lifespan of the real-life park that followed it. For example, if you take Connie Mack Stadium and decide not to move to Veteran's Stadium in 1971, you would not be able to ever move to the Vet. Your next opportunity to change ballparks would not occur until Citizen's Bank Park comes along in 2004.
This impacts franchise moves as well. For example, if someone selects County Stadium, which was home to the Milwaukee Braves in 1964, You could choose to not go to Atlanta Fulton County Stadium in 1966. So Atlanta would end up not having a team for the time being, while Milwaukee keeps theirs. Atlanta could then be eligible as an expansion city in 1969 or later.