Impossible to choose, but my favorite artists (not in order:) (And there are some I forgot but limited it.)
George Strait
Willie Nelson
Hank (Senior and Junior)
D.A.C. (besides the gimmicky songs, or underground albums) he is a good writer and singer
Pasty Cline
Arthel Lane "Doc" Watson (and don't forget Merle)
Loretta Lynn
Buck Owens
Emmylou Harris (and don't forget Gram Parsons)
Merle Haggard