Any aftermarket things that are not reversible will de-value your car.

Wheels are up to you..I can tell you 18 front and 19 rear works well.

Don't car for fixed lights.. In case you've never done this, here's a tip: When sitting in a Diablo you can not see the front end of the car. This can make parking, manuvering in tight spots a problem. My solution is to "open" your lights and you can see exactly where the front end of the car is (add 6").

Re: glass hood. I made one from scratch on a 355. Was thinking of doing the same, just for fun, for this car. Fiberglass frame with plexiglass and vents. Similar to Murci hood. Just not a lot of time for me right now. But if I make one I'll post it with pix here.

ps-agree that I would first upgrade brakes -if you have a good mechanic you can fit porsche turbo cross drilled with a very minor modification