Whilst Glass recycles his material even more than Vivaldi, I do love his music. The string quartets you mention are really good, and I think form part of the music for "the Truman Show". Saw the man himself playing his piano etudes, though I prefer tbe recording I've got with a proper pianist. Seen him with his band a couple of times too, once was a live music accompaniment to a silent film.
I think my favourite of his are the operas, particularly the "trilogy" -Satyagraha (about ghandi), Aknhaten, and Einstein on the beach. Saw the first two at the ENO in London. Dithered too long buying tickets for Einstein by which time they were £100 so left it, then for my birthday opened an envelope from the Mrs and there were two tickets - then read more carefully and it was a weekend in Amsterdam cheaper than the just the London tickets. Sat down for the show and notice some people pointing and staring in our direction, then realised they were
looking past us, so we turned and there was Phil himself at the end of our row.
Anyhow, did I mention I was a fan?