I, personally, would certainly include JWH among his masterpieces. A qualified masterpiece, though, because the last track, "I'll Be Your Baby Tonight" sounds SO out of place on this album. It's a good song, but it always sounded to me like it didn't belong there, especially as the album closer.
"New Morning" - A very good album.
In my opinion, "Planet Waves" approaches masterpiece territory but this opinion is shared by almost nobody. I'm not sure why I like it so much.
Cheers.
P.S. I haven't heard "Modern Times" yet. Hopefully soon...