While it’s no reflection of record sales, I’d say Billy Joel. Billy Joel’s peril was being too talented…so much so that he didn’t really find a recognizable sound. Take “For the Longest Time” and compare to “We didn’t start the fire”…the man has musical range that is really incomparable to any other major artist of the era. He wasn’t the most liked, he wasn’t the most bought…but he was probably the most talented.
Band? As far as American bands, I’d go with Aerosmith. They were one of the dominant ones, always did reasonably well with the critics, sold a ton of albums and had a lot of hit record. Overall, it would be the Rolling Stones as they didn’t – and haven’t slowed down that much in their 50 year existence.
Musician – Sir Elton John with hit after hit.