In our organization, Stream (like O365 Video) will be a primarily internal facing corproate tool, and that has some level of control around it. We follow a request then create process rather than self service provisioning model.
Please have it so that admins can designate which users can create channels.
This goes along with implementing an Owner/Contributors/Viewer model as well. A set of admins could create the channel, then designate Owners to do the more advanced specific channel configurations.