No doubt, Akkerman was WAY ahead of his time. In fact, in the '70's before EVH came along, everybody seemed to be sticking with pentatonic scales. Jan Akkerman and Uli Roth of The Scorpions were the only players I can think of who were playing "exotic" scales in the 70's. I mean, as far as they compare to modern lead guitarists, like your Marty Friedman
's, for instance.