Best year for rock'n'roll? Let's list a few candidates, I'd say:
1951: Jackie Branston And His Delta Cats (Ike Turner) playing Rocket 88. Hell, it's the first rock'n'roll record ever?
1966: You mention the very things that made it a great year.
1967: The Velvet Underground release the most seminal album ever, changing everything in the process. Everyone who bought it started a band.
1976: UK/US punk fully crystalises.
1993: Jarvic Cocker upstages Michael Jackson.
Gringo Starr said:
1966!
Revolver - Beatles
Pet Sounds - Beach Boys
Blonde on Blonde - Dylan
Aftermath - Stones
Freak Out - Zappa
Black Monk Time - Monks
Face to Face - Kinks
Psychedelic Sounds - 13th Floor Elevators
A Quick One - The Who
Fresh Cream - Cream
Fifth Dimension - Byrds
Love - Love
Animalism - The Animals
Boom - The Sonics
The Seeds - The Seeds
96 Tears - ? & The Mysterians
Web of Sound - The Seeds
Psychotic Reaction - The Count V
Turn On - The Music Machine
Jacques Dutronc - Jacques Dutronc
The Remains - The Remains
Small Faces - Small Faces
Another year that was equally remarkable was 1977!