I have an idea about the team games. Would it be possible for team players to set a maximum number of team games, instead of just "yes" or "no"?
For example: Player X wants to play a maximum of 10 team games. His captain can give him team games until 10 is reached.
Some players forget to set back the "Teilnahme an Teamspielen"-button back from "no" to "yes" and in this way it is no longer neccesary.