Check out Anathema - especially the later albums are gothic doom with ethereal female vocals and some electronics.
But my highest suggestions are fantasy/symphonic/ethereal black metal with darkwave aspects:
Midnight Odyssey
The Ruins of Beverast "Exuvia" (very trancey) & " The Thule Grimoires"
Summoning (Tolkien influenced)
Emyn Muil (Also Tolkien fantasy influenced)
And then of course there's dungeon synth:
Old Sorcery
Druadan Forest etc