I am interested to see the number on the GT500. My guess is the added weight is going to really be felt in its handling. The GT350 does well with its weight but at some point, that weight (and weight bias) are going to have a negative effect on its ability. Larger tires or not. I think it will end up being the typical GT500. A great straight line street bruiser.
I thought I remember reading the NSX performance numbers were 'meh'? Especially for the price. Or am I wrong with that?
One thing mentioned which I agree with is the mountain roads being wet. It isn't uncommon for them to be wet in the morning and many sections take a while to dry out due to the shade of the trees. So you end up with one corner wet and the next dry. Or entry dry and exit wet. AWD would be useful in that regard.
I still think the Turbo S is hard to beat as a car that is capable of doing it all. I get a lite car in the mountains can be a blast. But I think in other areas you will be upset with the lack of power. Plus they have the option to easily add power with just a tune. Or go balls out with intercoolers, meth, billet wheel turbo upgrades and so on. Their aftermarket is substantial. Go deep 9's and run a road course or mountain road hard if you wish to go that route.
I'm not against the GT3, the Cayman, GTR, etc. All killer cars. I'm sure you would be happy in any of them. I wish the GTR had a new generation coming sooner than later. Other cars have caught up to it in performance. Ca reviewers say it still does things it shouldn't be able to do based on what is is on paper. But also say it is growing long in the tooth. But again, it's a great car and had a great aftermarket. So another car any one of us would happily own. lol