Fuck yeah S&G!
Umm I really like two of The Vogues' songs, "Five O'Clock World"
(reasons to love this video are many; they include 1) backup dancers dressed in overalls and construction hats & miming factory work 2) extreme handsomeness, 3) yodeling) (all links are to youtube videos) and "You're the One."
I like the double lead vocal style.
Going by the OP's definition of oldies as anything before the 80s, I was basically raised on oldies, so...this would be quite an extensive list. I know Tina Turner is still around, for example, but her cover of "Proud Mary"
is one of my absolute favorites and it was released *looks up* 1971. (And Creedence Clearwater Revival do some great songs I grew up with as well, Bad Moon Rising
, Down on the Corner, etc.)
Speaking of covers, one really interesting gender flipping cover, where the cover became more popular than the original, is Linda Ronstadt's "Different Drum."
That was originally written for men to sing, it has lines like "I ain't sayin' you ain't pretty" and "You cry and moan and say it will work out, but honey child, I've got my doubts" which is pretty sexist but becomes interesting, if still sort of condescending, when Linda sings it.
Ooh ooh and I like couples duets, I could listen to Sonny and Cher sing "I Got You Babe"
for HOURS and I'm very fond of June Carter and Johnny Cash covering "It Ain't Me Babe"
even though the two have practically opposite messages, hahaha.
Just one more: Etta James singing At Last.
Whoa! OK, that's it for now.