How they've balanced the weapons and added weapons
You're pulling my leg, right?
Everything to do with the Promethian weapon set is a JOKE, and completely ruined the very fine tuned power wheel of Human and Covenant weapons. The additional weapons to the Human and Covenant segments are laughable and useless (this is going back to Halo 4, too), and they even had the audacity to break some of the better weapons while they were at it.
I played multiplayer at an event before release, and then post-release at a friends house once, and I was swearing in frustration the whole way through. I
especially hate the REQ bullstuff, and I prayed that it would be a DOOM-like situation (except, this was before DOOM had entered my consciousness).
I was so wrong. The whole package is a loving load.