1 - Bring back the career mode, fully featured like GT 1/2/3.
2 - Real time weather (not just rain) and time of day that effects the road/tires as an option for at least single/multiplayer races.
3 - Sport mode - but separate from the main campaign.
4 - A more realistic penalty system with negligent/malevolent players having to retrain to compete.
5 - Bring back the upgrade paths for cars, that was what gave the games life. NOT like NFS style.
6 - Also bring back the used/new car lot with every day cars as an option.
7 - The ability to adjust field of view, and further, more fine tuning of seat placement for in car view. Further further, ability to delete hands from wheel, or hands and wheel altogether.
8 - Optional toggle for VR racers to play in online matches with other VR racers, or regular lobbies.
9 - Better integration with current Streaming platforms.
10 - PLEASE bring back the classic Rally Stages and Hill Climbs, the current offerings in GT Sport are severely lacking.
11 - I'm sure there's more...
I'm by no means trying to sound negative in this list, I'm a life long fan of the series, been playing since GT 1 came out. I know how great the series can be, especially with the technology we have today.