While not strictly an instrumentalist, I still feel like Michael Hedges deserves mention here.
The first time I ever saw the guy was on Don Kirschner; he played a custom instrument which was a double neck acoustic; bass on the top and six-string on the bottom. It was set up as an open tuning and the song he played featured tapping, hammers and pull offs almost the whole way.
It was one of the most amazing performances I've ever seen!
They didn't call him "the guitarist from another planet" for nothing!
You don't think Clapton is better than him? What about Neal Young?
While I like Neil Young's work, it is very simplistic...just major and minor pentetonics. Very easy to solo to. People like Satriani use phrygian, myxalodian and other modes which makes their music more complex, and interesting IMHO.
If a nation expects to be ignorant and free, in a state of civilization, it expects what will never be. (Thomas Jefferson 1816)