I don't think it's a coincidence that many of the cars added in GTS' updates were from the PS3 era. I'm especially hoping for more race cars that could flesh out the major racing groups in GT7. In fact, here were my picks:
Gr.1
Audi R8 '05
Audi R10 TDI '06
Bentley Speed 8
Gr.2
Honda HSV-010 GT500 '12
Nissan Fairlady Z (Z33) GT500 '06
Toyota Supra (A80) GT500 '05
Gr.3
Audi R8 LMS Ultra '12
Unsure if Gr.3 or Gr.4
Autobacs ARTA Garaiya '08
Lexus IS350 GT300 '08
Subaru BRZ GT300 '12
Subaru Impreza GT300 '08
Gr.B
Audi Sport Quattro S1 Rally Car '86
Gr.X/Unassigned
Red Bull X2010 S. Vettel
Red Bull X2011 Prototype
Mario Andretti's Hudson
Notes:
We don't really need the N24-spec Volkswagen Scirocco, as I feel like the Scirocco Gr.4 is too close to it. I also feel like it's quite unlikely some race cars will return from the PS3 era. Specifically, the X2014 Fan Car, the Red Bull Kart (as it's just a regular kart with a Red Bull livery), the official WRC-licensed rally cars including the older ST205 Celica outfitted for rally, the Monster Sport and Tajima hillclimb cars, and lastly, the NASCAR machines. Regarding that last one, I think even if they did return, we'd really only need three at most for each of the three seasons represented in GT6, with one from each automaker, for a total of nine cars - and with one of them being the Jeff Gordon car we were tasked with driving for the GT5 NASCAR driving school. Ideally, and for similar reasons, I'd also like the Sebastian Vettel-themed X2010 over the other two versions, as well as the Citroen C4 WRC that we used for Loeb's event.
Ideally, if I were at PD, I'd forego including the actual NASCAR machines, and do something very similar to the F1500T-A, where there's a singular made-for-game oval racer. You also might've noticed I completely ignored the made-for-game touring cars and RM cars, as I think the more in-depth modifications system in GT7 will render those sorts of cars largely unnecessary for inclusion, though I'm fine with some coming back otherwise. Indeed, perhaps some of the touring cars/RMs will still have certain parts equipped that we aren't able to equip on the same model - such as the Corvette C6 or the Silvia S14 - even with GT7's immense set of options.