That’s a very succinct and apt summary. There is no getting around Waters’ talent. He was amazing in his heyday. (Though I do agree with those who noted that Floyd was stronger as a unit than as individual components.)
I was told that Waters made a pilgrimage to the place in Italy where his father was killed, and that it brought him a measure of peace. I hope it’s true; as you rightly noted, he was quite the loon in some ways.
There’s always been debates among Floyd fans who made them great, Waters or Gilmour. You’re very apt to notice that they are better than the sum of their parts, but I’d also add that Rick Wright was the one most responsible for their sound, and that their sound was what turned some rather mediocre pieces into classics.
... the music songwriting from the Division Bell and most of A Momentary Lapse of Reason is pretty terrible. The sound alone saves them. But you can’t say its because of the lack of Roger Waters; The Final Cut was disastrous.