aMember and Drupal customisation

I am building a Tennis Challenge Ladder. Player will register for free (Free Membership) so they can enter to play in a Tennis Competition (Challenge Ladder). Then they will be able to select what competition they want to play in. (I want to let coaches set-up these ladders without my involvement. There will be hundreds of these Ladders) Each competition will contain a list of players (A Ladder from 1 to 50 players for example) The player can select to challenge another player that is higher on the ladder than they are. If the lower player wins then they take the place of the higher player. I want to make the system operate so that every player can only play 2 matches on each ladder for free and then if they wish to play more matches then they will have to pay a small fee. (Set by me) I have attached 2 PDF's that show the process. I was planning on a system where a competition administrator can set-up new challenge ladders and each player that is allocated to the ladder can only play two matches for free and then they must pay a fee to play as many matches as they would like but only in that particular ladder. If the player wanted to join another challenge ladder then the same thing would happen. First 2 matches for free then they would have to pay a small fee to play more matches in the new ladder and so on and so on. A player could be playing in 5 (Any number) different ladders at the same time. Model 1. All competition providers can register free of charge. 2. All competition providers are able to set-up any number of challenge ladder competitions (Each challenge Ladder must have a start and finish date) 3. Competition providers can upload players and assign players to different ladders. (via CSV file upload) 4. Players can play their first 2 matches in each ladder free of charge. 5. If they wish to continue to play more matches on that ladder they must pay a small fee. Payment will enable them to play unlimited matches that are associated with that particular ladder. a. Individual payments will be done through PayPal. b. The competition organizer can pay a fee for all participants and provide access codes to the player they want to assign access to. They pay and then give out 20 special access codes to their players. 6. All ladders must have a start and end date with a maximum duration of 6 months. I hope you understand what I'm planning to build. I have already purchased and installed both aMember and Drupal 7. Kind regards Brenden Sharp