My file would be based on 1901 (mostly) to 2008. Franchise All Stars, meaning for example Dodgers would include Brooklyn and LA.
Then I had no players that were repeated on multiple teams. Great examples are Sheffield or Randy Johnson who had great seasons with several teams.
Then I tried to balance the power by distributing players who played on multiple teams to the teams in need. Examples: A-Rod/Randy Johnson both Mariners. Jeff Kent to NY Mets. Jose Canseco to Tampa. Pedro Martinez ro Expos/Nationals. Manny to the Indians, ect...
I usually favored offense, but not in every case.
Players imported with neutralized stats, with mostly career stats.
I went with the computer generated lineups cause I was about spent after creating the file. Cool thing is with 40 man rosters almost everyones favorites are there. But, as always, cant please everyone
I just hope people get some enjoyment out of playing with them, basically they are set up for single season play, I play out the games, switching teams every time seeing how well I can do
-Coop