Honestly I'm hoping that GR2 gets expanded in this game. With some of the statements Kaz has made about the best things about the past, present, and future, I really want to see the return of the early 2000s JGTC cars again. I.E., Supra GT, NSX-GT, and the Skyline GT-R GT500 cars. The GT300 cars would be rad as well, but not as important
GT300 likely will go into Gr.3, as they race alongside FIA GT3 cars in real life. Not to mention that two made-for-game Gr.3 cars, namely those from Subaru and Mitsubishi, have bodykits with a striking resemblance to GT300 cars. I'd love for DTM cars to be added so that Aston Martin, Audi, BMW, and Mercedes-Benz could be in Gr.2, but I don't see it happening due to licensing exclusivity for DTM. (Though the Group 1 cars that've been associated with DTM will become historic, given that DTM is now using GT3 cars for cost reasons, so maybe it could be easy to get those DTM cars, who knows?)
Anyway, if licensing proves to be an issue regarding DTM, it could still be fun to see what sort of made-for-game racers PD comes up with, and especially for automakers that don't have a real-world GT500/DTM car, much like how Alfa Romeo has a Gr.3 racer in spite of never racing in GT3/GTE/etc. And even for the automakers that have been in DTM, we could see made-for-game Gr.2 racers based on models that never were used in DTM, like the BMW Z4 (G29) or the third-gen Audi TT.
I want all the cars From GT1-GT Sport back again
Here's my proposal - at least have all premium cars from the PS3 and PS4-era return, with interiors for all cars including VGTs, but with some cars being left behind if licensing them proves to be an issue, such as for the Ferrari F2007 and F10.
I'd also omit most concept cars that later got production versions, with the exceptions being the Toyota FT-1 and Toyota FT-86. The second iteration of the latter would also be omitted, especially since it never had an interior IRL, so maybe the S-FR could also stay in the series, but not the racing concept.
Finally, I'd replace the GR Supra Gr.4 with an actual GT4-spec GR Supra, or at least update the interior of the Gr.4 GR Supra so it's not just the same interior as the normal, road-going GR Supra.
This would be on top of cars that were "standard models" but could get new premium models, like we saw in GT Sport plenty of times - the Toyota Supra (A80) being arguably the most notable example.