Player list in setup specification
The current specification only includes a unsorted list of player names. Don't we need the corresponding id as well, so we can associate player kits with player names?
I would suggest making it a list of player objects, where each object holds both name and id, and could be extended with individual configuration in the future.
We are also missing any team configuration, don't we? Maybe we include the team affiliation in the player object or add another list. (Just two teams, or an arbitrary number?)