TOD:
Film: "South Pacific", "The King and I", "Carousel", "Flower Drum Song", "Camelot". What they all have in common is conductor/arranger Alfred Newman who had one of the very best ears for orchestrations in Hollywood and worked with only the best. Among them were Edward B. Powell (his primary orchestrators), Shuken and Hayes, Earle Hagen, Bernard Mayers and Pete King.
Newman's team orchestrated "There's No Business Like Show Business", "Call Me Madam", "With A Song in My Heart" and a slew of others. Newman's orchestrators were second to none.
MGM had the legendary Conrad Salinger whose work greatly enhances the MGM musicals of the 1940s and 1950s, including "Brigadoon", "Show Boat', "Singin' in the Rain", "An American in Paris", "Kiss Me Kate", "Kismet" the orchestrations of which are swoon-worthy), "High Society", "Gigi", "Bells Are Ringing', etc., etcs. There are others involved, of course.
There are other film musicals which I find thrilling, orchestrationally, including "Porgy and Bess", "Gypsy", "Hello, Dolly!", "Goodbye, Mr. Chips", "Finian's Rainbow", "Mary Poppins", "The Music Man", et. al.
For Broadway, I have only my cast albums from which to register opinions, but DR Elmore hit all the ones I would have mentioned.