Cars:
Alfa Romeo GTV6 2.5 (1985)
Alfa Giulia Spider (1962)
Lamborghini Jalpa (1980s)
Original Toyota MR-2 (1980s)
More convertibles in general to take advantage of the VR environment. If I am being specific, then I'd ask for these:
Ferrari 348 Spider
Ferrari 365 GT/4 (Daytona) Spider
Ferrari 250 California Spider
Jaguar E-Type drop top
Any of the previously mentioned TVRs
Mazda RX-7 (1980s) Turbo II convertible
Spyker C8 Spyder
Maserati Ghibli Spider (1960s)
Would love to see Lotus return but I accept they can't come to an agreement with, I assume, Geely, hence Volvo also being absent
I think there's a big gap with Alfa Romeo that I'd love to see them fill. The Busso V6 is a legendary engine and is unrepresented in the game in roadgoing form. It has been there in the past in GTs, 156s, 166s and if I recall correctly, the 147 gta. I think the engine is best, though, in the 1980s Alfetta GTV6, which I think has had a previous vote and is also one of Clarkson's all time favourite cars (maybe that gets PD's attention..)
The Alfa Spider is another classic, previously represented as the boat-tail Duetto but i think the earlier Giulietta and Giulia Spiders are even prettier and would look gorgeous in VR.
I added the Jalpa to complete the 1980s Italian junior supercar collection (Ferrari 308, De Tomaso Pantera, Maserati Merak).
For tracks, another vote for Midfield, which I miss, and also I'd add Circuito De La Sierra from GT6. Not much to race on, but if you just want to drive road cars in a road environment, its length, nature and location made it perfect for a drive that didn't feel like a track day. With VR, I think Sierra would really come alive.
Zandvoort is also a decent track to drive on, fast and flowing.