It could be a lot bigger if they added stuff to do.Microsoft Flight Simulator Celebrates 10 Million Pilots - Xbox Wire
Microsoft’s longest-running franchise commemorates community accomplishments. Microsoft Flight Simulator is thrilled to mark another momentous milestone made possible by our tremendous community. Since the introduction 27 months ago of the latest version of Microsoft Flight Simulator, we have...news.xbox.com
I know it is a serious sim so can't go too out there, but how about Jobs, like crop dusting, putting out bush fires, delivering cargo to remote places, races(think this is in already) Tornado spotter, stuff like that. You could add progression for each job or at least tracker.