Just in case anyone here cares about/is interested in 'Ambient' music:
Up till now it has been predominantly affiliated with 'Electronic'.
And therefore it resides under Electronic in my Genre hierarchy table too.
But these days there are variants such as 'Ambient americana', ' Black ambient', 'Tribal ambient', etc.
So I think I will have to make some changes.
I could create a main 'Ambient' category and put everything with the word 'Ambient' under it.
Or I could put 'Black ambient' under Metal, Ambient americana' under Americana, 'Tribal ambient' under World, keep 'Ambient' under Electronic, etc.
Thoughts, opinions?
edit
to add some food for thought:
https://rateyourmusic.com/genre/ambient/