The community self-regulates who connects with who like any other social network/community. When you first logon you can explore/search for collabs and musicians and you will quickly identify people you'd like to connect with. If you are somewhat active the first few days you will quickly develop relationships with the type of people you are looking to connect.
Another important aspect is that the collaboration happens asynchronously. A lot of the frustration with forming bands is the synchronous nature of it. (1) all have to be together at the same time in the same place (which we know is very hard to do since people have their own schedules/priorities) and (2) all musicians have to actually perform perfectly in sync at once - any minimal screw up by just one of the band members and you have to start over. It's very frustrating. Asynchronicity solves those 2 problems.
For revenue, we have a freemium model, users subscribe to Bandhub Pro and get additional features.