In my opinion, the social relevent masterpiece is Pop Life.

His best work.

Purple Rain, When Doves Cry, SOTT, Pop Life, Gett Off

I think coming after the Purple Rain album and movie, Raspberry Beret was a brilliant single and my all time favorite!

not exactly my fav single, but i believe 1983's "little red corvette" was the most important single (and composition) of prince's career -- it got prince so much attention that WB released "1999" a 2nd time with even bigger chart success, and it gave prince an automatic (excuse the pun) audience for his album/movie release the very next year, making purple rain (the album) the best-selling album of 1984, along with "when doves cry" as the best-selling single of 1984.