Yeah I do think Richie is some what under rated as a guitarist. A few other names that might have been on the list could be Hank Marvin, Jeff Beck, Bryan May, Chet Atkins, John Mayall, Ry Cooder, Muddy Waters, Robert Johnson, John Lee Hooker and John Squire. I know some of these are quite well known, but maybe not for how good they are on guitar. Mayall, Cooder, Waters, Johnson and Hooker are/were all Blues artists. I watched a video recently where it showed them playing just with one battered old acoustic, and some of the sounds they made were amazing. It seemed like they were playing rhythm and also adding lead over the top at the same time, while singing and sometimes playing harmonica. I believe the guitarists I've mentioned above to be among the greats, and nearly all underated.