Don's supporting cast made him sound better than he is- I don't know how he enlisted Bonnie Raitt, Willie Nelson, Stevie Ray Vaughan and Ron Wood.
Eddie Money may be an average singer, but he's ten times the singer Don is, and Eddie came up the hard way: he was singing in NY bars while attending the police academy. Eddie wrote or cowrote all of his hits. He had a knack for appealing to us working stiffs, using blue eyed soul with rock underpinnings. He had left the secure future life of a NYPD officer by moving to the Bay area and it paid off.
Johnson was already a star actor, doing what all actors try to do: sell records while their show is hot. Even Donnie Most of "Happy Days" put out an album. It was in the cutout bin within weeks.