I think it would be cool to have some sort of ping system, possibly only for group members.
By ping, I mean a kind of alertion to tell another player they're wanted or needed if said person is afk. Outside of doing the whole discord group thing and other means to band together the people, this could be a way to grasp someone's attention. To make this not something people could abuse maybe add a cool-down to it. When pinged your little tab flares up orange or something.