The current WIP thread looked like a turmoil to me whenever I saw it. Certainly encouraging to see so much going on, but creators could benefit from keeping their topic open for a bit than until the next one posts anything regarding his own work.
If installed, such a forum could possibly host future competitions, too, if non-participants don't feel overwhelmed too much. I prefer "initiative" over "competition" anyway, so any prefix in the subject would suffice to put your WIP reports into context, may the thread last long or short.
Regarding the manifold subforums, I think we can distinguish two types of forums. I would call the groups "news" and "repository".
News means that people either report something or ask a question which is likely to be irrelevant in a month or a year. Examples are: Discussion of pending releases and news items from Facebook and other forums; screenshots and videos; WIP.
Repository means asking questions or reporting newly found solutions which are likely to be of interest in a year or two. This includes installation issues with specific add-ons, Steam help, and the content of the topical subforums (from route building to audio) after you subtracted the WIP reports.
The "news" style forums will next to no stickies, which shows more news on a page. The "repository" style forums can have 10 different pointers to tutorial etc. stickied and still room enough for a week's ongoing discussion.
I did not mention the fusion of screenshots and videos because I rarely ever look at the screenshots and never at videos, but that is just me.
