A lot of people have been gushing over the score, but aside from Enterprising Young Men and the end titles, I found it rather mediocre. Nowhere near the music of TMP, TWOK, TVH or FC.
In TMP there were plenty of moments to just sit there and listen to and admire the music.

Well, Giacchino can really only follow Abrams' direction about the music.
There really isn't an opening theme or score either, when you think about it. Just that one minute or so of haunting and almost sad music that swells and finally gives way to the chaos that builds at the end.
Frankly, I didn't pay that much attention to the music during the movie, otherwise. And, that's probably a good thing. It means a person is involved in the movie itself. Like background music in a restaurant. It helps set the mood, but you're still there for the meal, not the music.
As far as the closing theme goes, I would give Giacchino a lot of credit for being comfortable enough with himself to simply (and finally) give Alexander Courage's theme its proper cinematic treatment in full. In a way that was very generous of him.