Well, I did some tweaks this morning on the PC, and I think I will settle on these settings:
Display rendering quality on high (default is medium), no FSR 2.0, all other things set to auto except resolution scale, which is set to 100% (for 1080p).
I get a very clean look that gets to about 90 fps on average in the cockpit view, and up to 120 fps (!) on hood/bumper/chase cameras. There are some visual quirks here and there, but no noticeable stuttering, and so far, no crashes.
The GPU is working to about 98%, as it should, memory usage is 11 MB, and the CPU is around 70% in usage, so no bottlenecking.
Honestly, I don't recall it being this good at launch... Me thinks they would have avoided a lot of grief if they'd released the game as a "Preview"!