This is just a thought that struck me as I was going throught the Techniques forum.
It seems to me that a lot of the postings there recently are to do with aspects of airbrushing, largely the "Which one should I purchase and why?" sort of question.
There is , to my mind, enough postings about airbrushes and airbrushing to fairly constitiute a new forum subject, sort of in the same way you separated helicopters out of the Aircraft forum.
When it comes to techniques, I like to see more about working with aftermarket materials like resin and photoetch as they are something of an enigma to those uninitiated in using them.
Traditional brush painting techniques , such as washes and drybrushing certainly have their place in the Techniques forum, but airbrushing can be worlds apart from traditional painting techniques.
Theres obviously enough questions about airbrushing to take the lion's share of an existing forum, perhaps its time to give the airbrush its own space.
Just a thought, hope its a good one.