Hey,
Ok after looking at your tracks ive gotten this idea in my head:
The track should have to the side a big building which will be watch tower/vip room, infront of this i was thinking the type of pit lane could be there, and tht track could maybe curl a bit round to the sides but not to the extent you have came up with, i tried to create an example which you can see in the attachment.
The red bit and box is the track obviously.
Blue bits are to represent spectator areas although they could be much closer in.
The green bit is to represent a pit section, although i cant figure out what would be the best way to get cars down to the track since it will be dug down into the ground, im thinking some kind of on/exit ramp (maybe you guys can think of something i cant?
The Black bit is a watch tower building, with a nice VIP section, garage and shop (be about 2/3 stories).
Purple section is where i imagine racers can have tents/gazebo for preparing there machines.
Yellowish section is parking.
Grey area i dont know, just kind of random space could have stalls or something there.
If you could use my VERY rough image, to come up with something that is much more detailed and explain how people would get onto the track etc id appreciate it.
My dug down i meant like
http://www.fcac.edouro.com/web/pista.asp, funnily enough my idea looksa bit like there map, except they have a building in the middle which i think is a bad idea.