Rok2id, your question "Should we include the girl singers", just soaked in. Absolutely!
Nina Simone was forced to become a singer. She was playing piano at a lounge to pay for her education as a classical pianist, when the owner told her to sing. The rest is history.
That chick can really bang on the keys. Her early albums always included a couple of instrumentals. She has a style minutely reminiscent of Bud Powell, but it's uniquely "Nina Simone" one of a kind style. Sometime I single out all of her instrumentals, and just put them on my play-list.
Back to "Donald Byrd", check "Here Am I" and tell me what you think about Pepper Adams on Baritone sax?