Well, the problem is that the work on new tracks is very extensive and the time of most people is very low. I also would like to build tracks on my own, but I simply have no time to do it. I'm waiting since more than three years for the release of Nürburgring-Südschleife, and the user building this amazing track is really an expert on that, but it also takes a long time for him.
I would like to see every missing historical F1 track as a beta version in let me say five years, and maybe you could be the one to realise that.
If you are interested, please pm me.
TGF1DRIVER