This is what I was figuring. I just wondered if he'd done any kind of godlike innovation or something so instrumentally cool as to make me go "oh shit," and ignore the fact that I don't care for straight pop music, even if it is good.
Well, Prince never really did "straight" pop music, which partly explains why you'll find a bunch of decidedly non-pop people singing his praises. He often subverted conventions; look at "When Doves Cry" and "Kiss"—two of his most well-known songs—for example. Both are a stripped down, minimalist form of funk (funk, yet neither had bass), containing seemingly un-radio friendly rhythms (neither song sounded like anything heard on radio) and song structures, yet both became big hits.
Slight change of subject, I recommend you adventurous types check out Dump's That Skinny Motherfucker With the High Voice. Dump is just James McNew, bassist for indie rockers Yo La Tengo, and on this album he adds his own lo-fi spin on a dozen of Prince's songs, both well-known ("1999" and "The Beautiful Ones") and the more obscure ("Erotic City" and "Another Lonely Christmas"). McNew is certainly not the performer that Prince is, but he holds his own rather well; I dare say I prefer his takes on "Pop Life" and "When You Were Mine" to the originals (and with the latter, that's saying a lot), as he manages to find heartache and sadness in the tunes that Prince's at times too smarmy delivery never did.