I think you're wise to focus on subjective / personal impact rather than some kind of faux objective standards. Using the parameter of personal taste, this is always a fun and instructive task.

My list (you can guess my age from the choices), no particular order:

Roger (Jim) McGuinn

John Fahey

Lou Reed

Phil Miller

Jeff Beck

Honorable Mention: Jimi Hendrix, Andy Latimer, Dave Davies, Alan Holdsworth, Merle Travis