Hey thanks for checking it out, I hope you find something on the list you like. I’ve actually been listening to Stars of the Lid pretty regularly as well, and considered putting their album “And Their Refinement of the Decline” on this list, but thought it was getting too long already. That album reminds me of some of the droning bits from Sigur Ros’ early albums, especially “()”.
I also really like William Basinski, there was a while back where all I was listening to was “The Disintegration Loops.”
Hiroshi Yoshimura is a new one for me, I’ll absolutely be checking him out based on the other two artists you like.
I use reddit for music recommendations as well. I don’t find the larger subreddits all that helpful, but I’ve found lots of good stuff on the more specific subs, like /r/ambientmusic and /r/darkjazz. I will also find long genre specific playlists on Spotify or Google Play Music and hang out to it until something sticks out, and then I’ll be off down that rabbit hole.
As for Happy Birthday, I like all the songs on that album, but my favorite would probably be Happy Birthday Emily. I kind of wish that was the Adam song. :P