Groups
I think that it should be possible to set a group as a clan therefor you can be in multiple groups but you can set one of them as your clan. You would still have to post an app but it differs, There would be a group app and a clan app. I know you arleady have "Groups" but what i mean would be that a clan could have a little button that says "interact" and when you click on it, it would say set as group and if your not in that clan you can still do that but the leaders still have to aproove of the request. I hope you get what I mean.