As a custom race enthusiast, I would love to grind for hours to acquire the full grid of my custom races. First thing that comes to my mind is that we definitely need a stronger custom race creation system!
1. We should be able to create championships with full race week arrangements (practice, qualifying, and race)
2. The game really should extend the grid limit from 20 to at least 32. Some proper multiclass endurance races can be recreated for sure.
3. AI behavior enhanced -- AI opponents can actually use tactics, changing fuel maps, using different tire components on their own, choose to keep pace or to push and try to make overtakes. If the player pits in at first lap and choose not go out for the rest of the race, AI should just do their stuff, perform tactics and overtakes regularly, even with the absence of the player himself. Fix the weird rubberband technics, I don't want to see AI just deploying 90% of throttle on back straights ever again……
4. Add proper side by side rolling start. Add options of FCY, and safety car when accidents happens. It could just adds another level of immersive feelings.
5. We can apply liveries on AI opponent cars, so that we don't have to grind that much for the ideal grid.
5. We should be able to adjust the driver abilities individually of AI opponents in custom races
6. Up to date race cars and more circuits. Hell yeah I'll pay for it even if it comes with a pricy paid DLC.
7. Bring back old functions that are unavailable in this generation! For example: where is the full data display system in replays back in GT Sport? Definitely need that.
8. BSpec, BSpec, BSpec.
9. Fully deploy GT Sophy on all race cars and all circuit layouts.
Disclaimer:All of my statements only represents my thought, and with no offense, I genuinely thought that, a fully enhanced custom race system, can be a great way to make this game significantly better.