I would have replaced Dimitri Tiomkin's score for The Unforgiven (MGM 1960)
I would have replaced the sound effects and Daniele Amfitheatrof's score for Major Dundee (1965). Christopher Caliendo's replacement score is a bit much, too.
I would have replaced Michel Legrand's score for Never Say Never Again with John Barry's score for the remake of King Kong (1977).
I would have replaced Robert Cobert's scores for several of Dan Curtis' horror films including Night of Dark Shadows (1971) and Dracula (1973).
Network in the U.K. released Alfred Hitchcock's The Lodger (1927) with a BIG attention-grabbing score by Nitin Sawhney. I'd cut it and replace it with something else.
I would love to have heard what Jerry Goldsmith would do for Superman. Not because Williams' Superman is bad, but because I'm so curious if it would resemble or be vastly different from the work he did for Supergirl.
I would love to have Bernstein's soundtrack to the original "True Grit" replace the one in the remake. I would have loved for the makers of the new "Superman" to have used John William's score for the 1978 film.