More Oldies but Goodies like Nina Simone?

Hi Just found her a few months after looking up on google who sang the best Mr Bojangles.  She is classified as Jazz which i don't normally follow. I am a product of 1970's rock.

I have been trying to find more music like hers, I found Billie Holliday, Ella Fitzgerald etc by searching influences and related artists. ....  but their music sounds so dated in comparison.

Nina Simone's music doesn't seem dated at all, well to me anyway.

Research has led me to believe there were probably artists in the 1920s-30's etc that were just as good but the recordings are not good and therefore listening to them is not as satisfying.

BTW i found Nancy Sinatra i like her very much too but her discography of good songs doesn't have the same depth as Nina's.

Fellow music lovers, any suggestions of more like her I might enjoy

Post removed 
If you want to hear some roots of rock’n’roll, listen to Mahalia Jackson and Sister Rosetta Tharp. I believe Mahalia stayed with gospel music, but Sister Rosetta veered into secular music. If you’re into rock and haven’t heard them, you’re in for a pleasant surprise.