Breaking Dawn - Part 1 tries to be so hip that its modern music selections feel forced and out of place and as a result actually takes away from the subject matter being portrayed on the screen. The songs in the other films are more naturally matched to their respective scenes and with so much going on visually, subtle and less distracting music is definitely the wiser route to take.
I should probably also note the soundtrack, which is 75% shitty piano music, and 25% shitty pop songs. It’s hard to put into words how horrible the music is in this movie. Which is odd, because in Twilight, at least, the music wasn’t nearly as bad. Sure, all the songs were filled with angst and most of them were pretty bad, but compared to Breaking Dawn, the music in Twilight was amazing.
There’s also the rather frustrating constant musical interludes which splinter the film and prevent any momentum without really adding anything. Sure, there’s a nice use of Iron & Wine during the wedding which is not only a very pretty song but a nice nod to earlier scenes, but to convey emotion you need more than emotional music. Like decent acting, or a nice screenplay.