The Oblivion score really helped give that movie its identity.
A.R. Rahman's score to Warriors of Heaven and Earth is outstanding (before he did Slumdog Millionaire). Makes the movie way better than it otherwise seems. I rarely buy movie soundtracks (more often key themes only), but I immediately bought that one (pre-streaming). And I love Trevor Jones' (with some from Randy Edelman) score for Last of the Mohicans.
Music enhances so many movies. Certain musical events in Casablanca help make it what it is.
That music documentary you mention is streaming on Amazon Prime.