The Class calendar type is great if you already know everyone who's going to be attending. But if you want to fill up a class, then you need to manually add folks to the booking calendar.

It'd be great if we could have a Challenge (month of events for folks to attend), and then add people via a workflow instead of having to update each one separately.

Why do I want this? Because GHL doesn't have something like Add Event.

But this would be above & beyond Add Event because if the calendar event is changed, the all attendees would be notified of the update, which is a huge improvement.