Mmm, I didn't really want to give my opinion because every clan is different and what works for some won't work for others and vice versa. There's different guiding visions too, that affect the choices being made.
Though, one of the ways to increase forum activity is to model good forum activity. The leadership should all be posting as often as they can (ideally, more often than they can). Whenever the leadership's online, and a post hasn't been made in over two or three hours, that's the leadership's cue to make a post. Obviously they wouldn't be posting for the sake of posting, they'd come up a conversation starter or respond to other member's posts. By modelling good activity, the others learn to do the same; it's like monkey see - monkey do. If the members are seeing that the leadership is posting heaps, then they'll get the hint and realise they should too.
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