Maybe a add a menuItem to the channel context menu for that window. It's pretty damn hidden in the permissions dialog.

Also an extra feature for that window would be the abilty to show the content of "notifychannelgroupclientlist cid=3174 cldbid=2 cgid=7|cid=3174 cldbid=10542 cgid=7" etc so users with b_virtualserver_channelgroup_client_list can see who has which channelgroup in one channel.