BTW You mentioned ditching the jumps, but I think they're fine...
do you think so? I thought they felt a bit false (which they are!). The top-down camera shows them off better - from the in car cam they look totally wrong, but seeing as I'm reverting to the top-down cam only perhaps I'll leave a few jumps in and see if I like them.
I shall certainly be removing the dip-in-the-ground though - the car gets very confused if you drive in slowly or crash in the dip. Being single meshes I can make the entire track have slopes and hills, which should work just fine with the ground-following system - it's just jumps that are faked.
Turning of the smoke made the flickering go away.
excellent - I should have disabled it in first person anyway, but because I knew what the flickering was I got into the habit of ignoring it...oops!