I don't know how ES works when someone created an event in clusters, but it would be nice if there is an option in the event edit form to check or some setting to invite members to this event and it will send an email with the RSVP buttons (Attend/Not Attending)
Currently, all I get is the notification that a new event was created. That is kind of useless if you ask me, that notification email is good only for Cluster Owners who wants to know what's going on but for members, it's kind of like when I saw it, so? What? Am I invited?