What the heck (campaign spoilers)

First off, I love the gameplay. Thrusters and the gunplay are all top notch. And the set pieces were awesome. But that’s not what this topic is about.

This is the first Halo game that I’ve felt a little shortchanged narrative-wise. The cutscenes seemed very “filler” to me jus to set up the next mission, as opposed to more drama/story driving. And maybe I’m the only one, but after the Next 72hrs storyline, I kind of was expecting the Didact to make some sort of appearance or at least have his presence kind of felt.
I’m also not in love with what they did with Cortana. She should have stayed dead, and it wasn’t explained well enough how exactly she was transported to the Domain. I feel she just had such a good ending in Halo 4 that it should have not been messed with.
I may be missing a few things, or maybe I walked into this expecting too much, but I just didn’t get that “wow that was awesome” feeling after it was over. I know it’s a set up too, so if anyone has any input I’m open to it.