Well, 1086, like they say back on the farm, it's your tractor.
(I just made that up ....
)
I will admit that you have identified some interesting ways to reduce the weight of the car.
However, I agree with @
campy and your "car's diet" doesn't seem to go along with your driving objective:
"
I am a casual daily driver and on the weekend I enjoy spirited driving in the mountains/back roads/hills, etc. like I am sure many of you.".
Personally, I don't notice much difference in driving around the back roads, byways and in the mountains, whether mrs humfrz is along or not ...... and she weighs in at a bit more that 138lbs.....
I would think that proper tires and honed driving skills would net you more "comfortable" driving fun, than stripping the car.
humfrz