A limited slip differential is a performance, rather than a safety feature.
Limited slip differential - Wikipedia, the free encyclopedia
Cliffs notes: Regardless of the design, the implementation is that the more power you apply, the tighter the two driveshafts are linked together.
The traction control/yaw control package can be disabled with a cockpit switch. It's less of a driver's car because added safety adds electronics between you and the road, adds weight, and decides for you how to drive the car. But, as you said, it can be disabled. I can't recall how Honda's skid control works, usually it's some combo of pulling timing, closing throttle, applying brake to one wheel.
The headrest speakers from the earlier versions were a different design, more tacked on, than the ones that are now integrated into the headrest. It's a dealer installe option, so probably a 10 year old child can do it
If you can fit in the Elise, you'll have no problem in the S, any year. After driving my friend's Elise for just a few miles, getting back into the S felt like getting into a '78 Eldorado
