This makes the most sense to me. For what its worth though I'll extend the thought...
If I look as some other boards I check in on, there are exactly 3 possible child forums to post in for a given genre (and NO posting directly off the parent): Completed Builds, WIP, and General Discussion of the subject (which could include anything from discussing various kits in the genre, to discussing what color a certain tank/plane/mecha is etc.).
ANYTHING to do with construction, tools, paints, techniques etc should NOT be in the genre discussions because those sorts of things benefit all and we can cross pollinate as such (for example a discussion on scratch building stowage for AFVs would be of interest to the SciFi crowd, figure painters, airhead, everyone as they can apply that to their respective disciplines). All that stuff should be under "Construction and Finishing" (or whatever) with various child forums for construction, paint, etc.