In some cases Zelda games have touch on this using midi voices. But being that Midi voices are really not that great is probably one of the reasons your idea has never been realized.
But I would agree with you. A 100 piece chorus could be epic! And I have a feeling we may see some in the new game.
How about this, it's a
must see/hear YouTube - Preliator/Zelda
(anything by the group Globus (like that song) is epic)