Suggestions:
since u planning on making friendship level here is some suggestions.
1. If u make 1 out 4 of them mad or upset whatever that call, they will force u to run a certain amount of hard map based on thier negative friendship level
2. Make all of them mad then they'll force u to play a special map
3. Make thier friendship level to a certain amount of number then they'll give u access to play their map