"replacing nature for something humanly introspective" -- this seems self-contradicting to me.
Sounds are just another means of composition, and can be used in ways comparable to, and in many instances more effective than conventional instrumentation (imagine the melodies from BURZUM''s
Hlidskjalf on a concert grand piano).
Drone stuff like LULL, LUSTMORD, FINAL, etc: These guys focus more on atmosphere, and should not be seen as
compositional - as in the style of Classical music, particularly Beethoven - but as
meditative - like Tibetan Singing Bowls. I have read little about it, but isn't the ability to dismiss attributable phenomena as having inherent
character one of the goals of Zen meditation?
Personally, I don't like the drone/noise/dark ambient stuff, but here's what I recommend:
One of my favorite artists ever is MAEROR TRI. You can download their stuff
here on Audiofile. I recommend
Hypnotikum I,
Myein, and
Yearning for the Secret(s) of Nature (in that order). A group formed of two of the original three members, TROUM, is supposed to be good, but I haven't heard it.
As mentioned above, TANGERINE DREAM are also exceptional, and stuff by a former member of theirs,
KLAUS SCHULZE is similar.