Seems like I'm not the first to suggest about this, has been proposed already some years ago but those threads are already closed:
http://forums.autosp...ents-subforums/
Whilst I agree that too many subforums would destroy the board, I think that one non-F1 subforum would enhance the forum. I think one non-F1 subforum would prevent non-F1 topics getting buried within F1 topics, yet one would be enough at the moment. I think all non-F1 topics opened this year would be on the front page of the subforum. And I don't see it as a problem that there'd be everything from NASCAR to WRC and MotoGP. I think that the least versatile fans are the F1 fans. If you care about other series, you're probably interested about more of them, so having more non-F1 series in the same subforum wouldn't be a problem. And of course, if the subforum would become very MotoGP/NASCAR/[enter series name here]-dominated, that series could be split to another subforum. Of course, there'd be the dilemma of general motorsport discussion from the F1 point of view. I'd keep those discussion in the F1 section. Examples of those topics could be "Works team budgets/sponsorship income in other series in comparision to F1" or "[Enter F1 driver name here] goes to WEC/NASCAR".
I know, this hasn't been accepted in previous years but let's see if the opinion has changed. I think I've seen many posters saying their interest is slowly switching to other series, so maybe this idea will get more support this time. Plus this would split RC only to two forums instead of previous suggestions with more subforums.