I'm half looking forward to the cars, but also the other stuff that'd be coming with the update, like QoL changes, possible tracks, or just other stuff in general. Keep in mind that even outside the stuff that could come back from GT6 or be new altogether, there's still some prize-winning cars that will likely come back at some point - there's the other Pebble Beach and SEMA cars, but IIRC there was also a temporary period that PD picked out cars from the Tokyo Auto Salon, too, like the D1GP RX-7 FC that's been in GT4, 5, and 6. Not to mention that I really look forward to how they'll update the older prize-winning cars, like the HPA Golf, or the Buick Special.
EDIT: Minor question. Does BoP only apply to Gr.4/Gr.B/Gr.3/Gr.2/Gr.1, or does it also apply to the N-series? I also wonder if other groups could be created other than the one that may've been leaked, and if there could be a group that'd be ideal for the Jaguar XJ13 and the Ferrari 330 P4? Maybe those two could be retconned to be put into a new group, too - I think the BMW i3 and the Aston Martin Vulcan used to be listed on the official website pre-launch as being in different groups as opposed to the groups they're actually a part of in-game.