1. While we tend to believe that player mobility is mostly a product of free agency, and that "in the good old days" most players stayed with one team, this doesn't seem to be true. While conducting my 1934 replay, I also replayed 1931. A great many players were on other teams only three years earlier. This didn't include only journeymen, but truly great players like Rogers Hornsby, Chick Hafey, Chuck Klein and Stan Hack.
2. Baseball players did not "work out" in the 1930s, or seek to develop their physique. At the time, it was thought to be detrimental to their flexibility, which was thought to be more important in a baseball player. This seems to be the mentality in Japan. New Royals' skipper Trey Hillman will reportedly use flexibility training as a way of improving his team's conditioning for 2008.
4. The 1930s was the era of nicknames - the weird players were the ones that didn't have one.
5. The public persona of Dizzy Dean was highly misleading and a deliberate distortion of a man who realized he needed a "character" to sell himself. In public, he was a colorful country rube, who couldn't pronounce the King's English and couldn't care less. In private, though, he was a well spoken, refined family man and friend.
6. The 1930s teemed with great players, many of whom we are familiar. Many others, however, such as Lon Warneke, Chuck Klein, and Red Ruffing deserve to be much better known. Part of the problem is that there aren't a lot of books on the era. A new, comprehensive treatment of baseball during this era is definitely needed.
8. The Society for American Baseball Research (SABR) has a fascinating biography project underway.