Yea, civil rights had improved from 1956 to 1966. But in terms of marketing, it was still a safer bet to have 3 white children on the cover; than 3 black guys. I do wonder though, if they came out with the re-release as response to his growing popularity. Or as a filler, while he made the transition between bands.
Sure, His First recording of Carmen is probably one of his best recordings incliding Delilah from way back. BTW The album Swingin with 3 white toodlers on the album cover was to make his album more "Mainstream", too bad that was nessecary those days. Thehe original name of the "Swingin" Album is "Ramsey Lewis and hil gentlemen of swing