(I'll add as I can remember)
Led Zeppelin's Last Album released just before Bonzo passed away, I think.
Carmen - The Gypsies. Tony Acidhole Visconti dumped the band with 3 excellent albums, but made sure that Jethro Tull took away a magnificent bass player that helped Carmen rock! John Glascock. The guitar player, doing spanish licks on an electric guitar quit playing the elctric guitar and has never touched it since! Real shame, that such a great player can not be appreciated!
Quatermass -- both the first and last of their albums. But the strength and beauty of this album was never duplicated by any of their members anywhere else, up to and including Peter Robinson who went to be reasonably well know for a few things that were ... crappy! ... by comparison!
Aphrodite's Child - 666. An incredible amalgamation of anything, everything, and whatever else, was a great album, that I doubt most Frank Zappa fans will ever bother sitting with and listening to. But some folks are so dang superstitious that the Aegean Sea piece alone will take them away to their crematoriums ... and let them die unknowingly! One, very famous man came out of this group, and he has an Oscar in his closet for a soundtrack or two ... btw!!!! But would a Zappa fan give a shit?
The Doors -- LA Woman ... is there any doubt?
Duncan Browne - Streets of Fire. The gentleman died of cancer at a very young age and his style and quality was completely taken by Dire Straits a good bunch of years later!
... and on the cheating list ...
Fairport Convention - Rising for the Moon -- The last cut was Sandy Denny's last. Strangely, the song was called "One More Chance" and she didn't get it, and the way she sings it, it's almomst like she knew it, anyway. To make it worse, the "Remastered" album has a version of this that she plays it on piano alone, and it is just as haunting and pleading as this one was. For me, Fairport Convention died after that song, and all the material since then is meaningless and lacks the depth of the soul, beyong just another jig, as if we were all drunk! Worth the listen, to one of the prettiest voices ever, and the two songs that she put together for this band ... that stand out a ton ... "Reynardine" and this one. If you have never heard these, you do not know what beauty and care and understanding of music is all about! You just know rock'n'crap!