Just re-visited this thread that I started. A band that I haven't seen mentioned is ELP - Emerson, Lake & Palmer. They were waaay ahead of their time. They were very hot for a while, and their music spans several vibes. A few hits:
"You Turn Me On"
"From The Beginning"
"Lucky Man"
"Fanfare for the Common Man" (their version of it)
The band Yes. Lots of great music came from them. Progressive rockers. A few of their hits - but not all .........
"Owner of a Lonely Heart"
"Roundabout"
"The Calling"
"I've Seen All Good People"
"Changes"
"The Rythm of Love"
"Leave It"
"Love Will Find a Way"