Cars:
-Porsche, anything Porsche (premium) even if it's Ruf
-Pagani Huayra
-Koenigsegg Agera
-Mclaren P1
-LaFerrari
-918 Spyder
-McLaren F1 GTR
-GT3/GT2 spec cars
-Ariel Atom/ cars of the sort
-Old/New F1 cars (with a built in F1 league like what F1 2012 has)
-More BMWs, More Audis, More Mercedes (especially old ones)
-More Ferraris (Dino, 288, F50, 250, etc.)
-More European cars, less Japanese cars
-More premium cars (make the Premium:Standard ratio about 1:1 or more premium)
Tracks:
-Infineon
-Seoul Circuit
-Seattle
-Brands Hatch
-Hockenheim
-Old Nurburgring (Sudschleife + Nordschleife)
-All rally stages from the past (Swiss Alps, Tahiti, etc.)
-Complex String
-El Capitan
-Add some "freestyle offroading" like a large desert to free roam in