OK, I'm something of a game spoiler sometimes... How about putting all posts about modelling in one forum, and then having a really good search engine that lets you prepare a list for youurself - with all posts about german aircraft in 1:72, or all posts about gravity feed airbrushes, or all posts about humbrol paints, or all posts about decals printed in italy?
'Cause if we split the forums really fine enough, we will have categories with no posts at all or just one post in them, plus lots of mis-posted posts (hey, wrong category!) and most viewers will use "recent posts" anyhow.
For now a zero-cost solution is to take a good internet search engine of your choice and type: cs.finescale subject - where subject is what you want to find. This way you can find pretty good matches.
This could be smartly supplemented with an AI program that would tag the posts to help with searching - like when a poster types, for example "Iwata" the post gets tagged #airbrush.
Awright - thanks for reading and have a nice day
Paweł