Thank you and welcome to the forum Samuel.
I use a leather custom bra when I go to the track. Other than that, I don't as of this time, but that may change.
I don't sweat the undercarriage of my car all that much. The only thing that I make sure of is that no fluids from the motor are staining the undercarriage. Other than the wheel wells, I leave the rest alone until I roll up under the car.
Jacking a Corvette up is quite an undertaking without a lift. In order to raise my car in the garage, I have to go through the lifting steps you see
in this thread. It takes about 15 minutes to get it up off the ground. You can only lift a C5 Corvette in 8 spots.
Convertibles are nice but I don't see myself ever purchasing one. The coupe give me the option of a convertible and a hard top all in one. Plus it offers shade when the top is off.
Number 1, if you are using the correct technique AND a quality towel, you won't create any scratches. Right now, most of the best microfiber is made in Korea. You will not find them in any auto stores, you have to order them online or from a product line distributor. Right now, Adam's and Zaino have the best microfiber that I have used. You don't use one towel for everything. There are towels specifically for drying and towels specifically for removing polish and wax. Use the right towel for the job you're doing.