Managing channels and adding members can be improved by introducing so-called circles.
Circles allows the administrator of Mattermost to create their own groups of user/member. This feature could be used to reflect the responsibilities and communication strategy of an organisation. Those groups of members (or ‘circles’) can then be used to add them to a channel. This will improve the maintenance of configuration of channels as you don’t have to add single members to a channel.
In addition it would be valuable to have the possibility to inform circles in a channel by writing @circle-name in a chat window.