We already have the KTM X-Bow GT2. The GT-XR is highly similar, just the road version with less aero. I don't expect to see it, since it would need a complete new model but wouldn't give the feeling of getting a complete new model (low value for money on the modelling front).
The DeBerti C10 Slayer is awesome, but not sure if it fits the track day / track toys vibe. It's more of a hot rod. Does it actually do corners?
Edit: Road and Track's 2024 best track cars:
We have most of the cars on that 18-strong list, but the 2023 911 GT3 RS is missing, as is the latest Civic Type R (the FL5) which is also missing.
It also lists the M4 CSL which would be good, but probably not as good as the M5 Comp since we don't have that generation of M5 in the game yet.