When you try to keep your teams balanced, are you balancing them by flight? You may instead want to try balancing your team by handicap when you automatically build teams under the tools menu choosing option "#8" (Maintain equal team handicap).

Be sure to do this after you have locked whomever/(your players and coaches) on their teams.

If there is only one box checked when you automatically build teams, you have a better chance of no 'repeats' during your tournament.
Unfortunately, the more boxes you have checked (when you build your teams automatically), it limits what the program can do.