Wireless headphones are totally worth the big investment. I have a pair of Pioneer 5.1 wireless that I've had since Halo 3, and they're still amazing.
Which brings me to my next issue with the sound of Halo 4: your footsteps are indiscernible from everyone else's. It's annoying to stop and turn around, thinking that someone is coming up behind me and it's just my stupid clunky feet. I know there's a perk for that (ugh), but I prefer Firepower or Stability over stealth for the most part.
I'm also ready for Camo, Promethean Vision, and Jetpack to be obliterated out of personal loadouts. It's great playing the new maps, but the same shitty habits of cowering in a corner using Camo, taunting approaching players with PromVision, and destroying intended map design with jetpack doesn't do the new maps any favors. Any time now. Seriously.