There are geniuses in every style and genre of music, and they play every instrument. As a guitarist, I've always been interested in other guitar players. Excellence can come in the form of virtuoso solo and facile lead playing. But it can also manifest itself in rhythms and tunings, and very different approaches to the instrument.
Someone who took acoustic guitar stylings to a different place was Joni Mitchell. Her Martin D-28, tuned to different open tunings, presented both a challenge and a roadmap to guitarists in the late '60s.
Here she is doing Both Sides Now:
Here's Chelsea Morning:
Big Yellow Taxi:
1966, Circle Game: