Despite that, my impression is that we mostly have clans of oldtimers and inactive people, who have either moved on to other games, or grew up and have little time for Toribash anymore. It seems that when people get a good hang of the forum it takes little time before they lose interest in the game.

Maybe that's because a lot of people don't have contact with the forum right from the start.
Suggestion that might deserve a thread(?) - adding a button on the menu ingame that would redirect people straight to the forum would likely make people forum-active right from the start and we could have more people participating on this kind of events??