tire pressures, toe camber and spring rates, we would love the option of having left/right in addition to front/rear.
This is especially important to oval racing where the left side of the car runs positive camber.
Having a weight jack/wedge. To adjust weight balance for oval racing in applicable cars such as NASCAR/INDYCAR.
Tuning the boost levels of turbochargers
Fast and Slow bump and rebound adjustments
Cockpit adjustable levels of traction control, differential lock, ABS, and fuel maps on cars that have it in real life ie GT3, F1, lmd-h, etc.
Being able to open and close brake ducts. Having too hot of brakes causing fade/decreased brake performance