Thank you for posting this, Ian.
I agree with what you said. Even though I listen to a lot of avantgarde contemporary classical by other composers and to avant-garde jazz, every time I return to Stockhausen I am, without exaggeration, just shocked how original his music is, despite all that other music that is pushing boundaries. It is on another level of originality. And yes, this stretches to his last works. The KLANG Trios were written in his final year, and the ones that I like most are BALANCE and TREUE. I return to these incredible compositions over and over again, and each time I marvel at the fact that there is just no music like them. As I wrote in my essay about the Trios:
"For me personally, puzzlement about the compositional strategy in these works has given way to endless fascination with this new kind of composition, which results in music that breathes in a unique manner."
And who can deny the utmost melodic originality in WOCHENKREIS? There is just nothing like it, and its combinations of formula fragments into melodies stand unique in all of LICHT as well. And of course, the early works also remain fresh as ever. Currently I am diving again into his early PIANO PIECES from the Fifties/early Sixties.