I say Jimi Hendrix, and I say some of his Live performances were really good as according to the eyewitnesses, even "the Who" (who were well known for their stage antics and all that" were afraid to play after Hendrix took the set...Even the Rolling stones felt threatened by Hendrix' s Live performances.dun let me even get started on what clapton thought about him..
Yes, Hendrix did sometimes sound pretty bad, but you'll have to blame that on the era he was in,most of the time people complained about his guitar being out of tune and his over-indulgent solo-ing and stage destruction, I blame that on the lack of Korg DT-10s and the fact that his guitar was tuned half step down and also he loved to whammy like a mad man with the vintage tremelo units(they weren't built to withstand that much abuse then)- also, I blame the drugs he took to remain sane with the hectic touring.
Influential?read roger mayer....check.Revolutionary?The first african american man to transcend the boundaries of segregation thru his music circa the post-rosa parks civil rights movement in the USA?Check.