If you could bring back one great artist that has

Jimi and Duke Ellington were the first two names to spring to mind, but I think I agree with the choice of Beethoven. His very late works were getting kind of strange (some critics I've seen have attributed some of that to possible hearing loss) in a very interesting way. Aside from being an immense talent, he was a guy who died while his art seemed poised to take "the next step".

Still like to have Jimi and the Duke back, tho.