Quite like this idea, truly. But what if the group isn't online, someone see's the group on the list, clicks it, and sends an invite? Then the group comes on, and sees it. They decline it because they no nothing about this person.
That's why I would like to say this, though correct me if I didn't get your game idea right.
What if the group, currently accepting, makes a form for those who want to join, and when someone wants to join, they fill out the form to join. Then, when the leader is online, he/she can accept or decline.
Then, when the joining member is on, he/she can come on, and see if the group accepted.
If the leader accepted, then the person would be in the group as soon as the leader accepts.
Also, if the group has a map, they could write "Unmapped" in the bio or something like that.
And if it's mapped, they put "mapped" in the bio, and when the bio is done, they can put the link in a little window (leader only) and once the person joining is accepted, the map loads right into Cape or somewhere else, I thought of.
Eh, just thought I could have an idea for this too, no? :3
I truly like your idea though. Man, why can't Kov come back some day? Hope he does...