We tried this policy but is annoying for user create each channel for use, a minimun quantity of channels for group is necessary, in my case I hold a ts server for italian gamers, we do it for free and for that we give to each group of users some private channels, statistically the groups is around from 4 to 20 users and they need 2 to 6 channels each, some groups, in the lifetime o server, sometimes, they leave or don't use some channels, this requires a periodical clean of channels for maintain the server easy to use, however this process can be automated if a bot check if a channel is used or not like a idle of the users.