As about the channel creation i guess you can allow them to create permanent channels in specifi parent channel (by setting up the correct permissions).
As about the automatic deletion you can use the JTS3 Server Mod Bot by Stefan.
It has an option to set specific channels and subchannels to be check and if they are inactive for the period you set they get deleted.
You can use SinusBot and this Script: Private Channel Manager | SinusBot Forums for creating chnnels. Simply specify a channel that the client must enter and possibly a server group that the user must have. The bot can then create a channel and gives the user channeladmin.
That’s an easy part. Unless you want a specific server group to do this, then Instead of granting permissions to a server group or channel group, you need to grand permission to these channels. With this way, every user will be able to create his subchannel bellow the parent channel.
p.x: in channel “game room 1” grand the permission 'b_channel_create_child" and any other permission you want (like temporary channel or permanent channel, allow topic, description etc.)