I have been an "Optimal Build" feller for quite a while. My idea has always been to build this car into the best car it can be, and then find out where it runs the best. As you pointed out, the initial characteristics of the car can give you a hint as to which way to go. The TSX is a good example. To try to build it for Positano would be an extreme waste of effort. And because of its weight, it would be a mediocre "track car" at best. But to build it as you have, as an oval car has taken the best characteristics of the car and exploited them to where the car has value on certain tracks as far as being a "Track Attacker" is concerned.
That is one of the reasons for including Amalfi Coast in the list of QR tracks. It is good to know which cars will do well on Amalfi, as well as those that will not. My Fiesta has my best time on D Amalfi at the moment, and it doesn't show so puffy on Sebring Short. That is information I can use, both in car selection, but in future tweakage sessions.
Once the cars are built, and tested with the QR, then the balance of the 103 tracks can be run with the best car(s) for the purpose. At least that is my plan.
But then there is the BCG project - my goal with that is to take one car, one Toon per class and run the whole game with it. I spose that is taking "Optimal" to a whole 'nother level.
Good luck with your project. Let me know which track you decide on for a QR Twisty replacement. We were looking for one when Amalfi was decided upon...

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