I would definitely say these two should make the cut (and indeed are better than some in Wally's list):
Tor Poznan (laserscanned, as far as they say)
There are a few others that are good enough:
Misano (we used it ok)
Bilster Berg (only for street cars, but the track is a lot of fun---track is not available anymore... long story...but I and a few others still have the file)
On the ones mentioned by Wally: Luccaring worries me a bit in terms of GPU handling it with 20 cars in it; Baskerville has a few issues, but in a big-pack street car race I do not mind it. The best ones seem to be Donington, Riverside, Paul Ricard, and maybe Modena.