I'll second that, Bathurst (or Mount Panorama, to be precise) is a great track, I've only driven it in TRD2 and it's fantastic.
Speaking of precise, I've got no idea what the proper name for this course is, but the version of the Nurb that F1 ran in 1973 (the only year I know for sure they used that particular track, I'd assume they always used that version of the Nordschleife) would be great, with that neat banked bit at the beginning. You can sort of see what I'm talking about, with the 'b' shape running into the present day GP course in
this image.
A few more tracks I'd like to see -
All the versions of the Paul Ricard circuit, with its fun blue and red futuristic runoff area things that I really don't have a clue how they work.
I can't forget my 'home' track of Mosport -
I'd imagine a lot of tracks like Spa have been mentioned a thousand times so I won't bother with them, although obviously I'd love to see them there.
Norisring -
Monza Florio -
An rFactor lap of Monza Florio
I'm a sucker for any track with a legitimate banked curve as well as any track with random shots through a heavy forest, so naturally, I absolute adore this version of Monza. Add in the Monza 'bowl', while we're at it.
We can throw in the
old/real Hockenheim while we're at it.
A1/Osterreichring -
Montjuic -
I also wouldn't say no to the Bergrennen hillclimb course, and the full Pikes Peak. And you though GT4's Grand Canyon course was scary..
EDIT: And how good I forget, Vallelunga!
Fiorano/Misano/Mugello.. Imola.. bit of a theme here

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