Thanks for the comments, guys!
The explosion and gun sound effects that differ from what you're used to are indeed part of the new combat sound overhaul. They might have been post-processed in post production to make them "sit" in the trailer mix, but they do reveal a small glimpse of what the newer sounds are like.
Both Hollywood Strings and Hollywood Brass sample libraries from EW/QL are part of the musical score, but there are a lot of other things in there as well. I get asked a lot about what software I use, and I always try to remember emphasizing that it doesn't really matter what software or samples you use, it's more about learning to use what you have.