I like Goldsmith. Prefer "Rudy" if going with only one. If we are picking only 1 movie, I would go with Howard Shore and any of the "Lord Of The Rings". He composed a lot of different themes for each character along with The Shire, the Battles etc. Phenomenal work. Regarding Horner, Williams has nothing close to "Glory". Horner vs Williams is like comparing Lennon to McCartney. Extremely different composers.
Howard Shore has been on my radar ever since
he played in Hamburg in the underground clubs, no sorry that was the
Rolling Stones, no, no that was another band that's currently eluding me! Anyway being a David Cronenberg fan, I was impressed with the Howard Shore scores to his early 80's movies like Scanners, Videodrome and a little later The Fly. And it's been interesting following Shore as he went on to bigger but not necessarily better movies and yeah, his Lord of the Rings soundtrack fits the movie pretty well.
BTW I listened to excerpts to the "Glory" music and it's fine, if not a bit derivative and generic.
JohnM