What about allowing users to add channel group permissions to users that are not in their room?
I’ll make an example:
User x is in the welcome room, and user y wants to let him join his password-protected room.
There are two ways, giving him the password (that may change in future) or giving him the “join” permission (server related, not present by default).
The current bad thing is that the user needs to be in your channel in order to assign him the join permission, quite bad thing.