You're initial feelings are pretty much inline with mine... except heavish is a bit of an understatement in my case.
I'm still far from happy with my settings, and having them reset to default every time I exit (and re-enter) the game isn't helping. I had them a bit better before but didn't bother to write them down thinking they'd save (like the game says they will

). This time I took a screenshot so I can continue to tweek things (I hadn't started on Speed Sensitivity yet, that's why it's on zero).
View attachment 846703
I don't know if you remember when Circuit de la Sarthe was introduced to Gran Turismo (5 maybe??) everyone's wheels were getting a death rattle down the straight, that's one of the same issues I'm fighting with this game
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.
If anyone has any suggestions I'm all ears.
Ps: I'm still having a ball regardless of a few issues 👍
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.