I've mentioned this idea before, on other threads, but I'll repeat it here because it makes sense to me.
If I ran a model company, my company's website would have a very prominent area where people could leave direct feedback as to what new kits they would like to see. Either an open-ended "let us know" type of thing, or a list of possible subjects the company was considering, to allow people to vote for the one they would most like to see (configured so that every person could only vote once, maybe via cross-linking to your email address or some other way to prevent people from stuffing the ballot box).
I know that the model companies keep tabs on the various forums, but it seems to me that having a place for direct customer feedback on your website would be a logical thing to do. It would offer the manufacturers a way to directly gauge the interests of their customers. I don't know why all kit manufacturers don't so that. That sort of information is something I would definitely want to have if I ran a model company.