I think this can still be improved, maybe a system where those who purchase the group package can put the free spots to be listed on the site, and add a way for users to just "apply" to it.
But more than anything, I need people who are willing to put their money where their mouths are. There is nothing stopping people to purchase those packages and offering to their friends or other social networks. It would also help quite a bit to solve the onboarding issues.