Another aside:
Splitting subforums by specific game/type rather than activities like actual play, design, etc, can starve discussion (if everyone goes to general and there's not quite enough traffic), or pour them in concrete as the "identity" of What We Play Around Here (if there is enough).
If "Keep the playing field fairly level to let new creators rise" is a desired value, which seems pretty, y'know, in keeping with the site... It might be best to split solely by activity at first, and only by game as/when needed because one is or feels like it's dominating the general conversation.