My biggest disappointment is how they embellished so many of the classic songs and added a couple of new ones, but didn't use anything from the musical. I desperately wanted to see Gaston's proposal song, 'Me' in live action, and they use some material from it in the lead up to 'Gaston' (the bit about a rustic hunting lodge, little wife massaging my feet, etc), but no. The only big original number we get is the Beast's solo, which was admittedly very good.
The even left out 'Human Again', which was in the Disney version, albeit the DVD release.