The most refreshing part about a lot of these complaints is that they will be a lot easier to fix or adjust. No changes are really needed to the actual game physics, or even the weapon settings. It's all little setting adjustments here and there, at least I hope. Each Halo game outside of the first one, since it wasn't on Live, has had multiple fixes after release. I think 4 is in a good spot for the moment, assuming 343 will listen to the feedback and make some honest adjustments. Worrying about kill cams is a waste of time though and I think it should be left alone, personally. Not worth time and resources.
The hardest fixes, if 343 even wants to try, would be the Ordnance issues, adding red X's where people die, and changing JIP to like a social playlist only. Changing up the playlists, and what AA's are available, along with radar/no radar seem easy as pie in comparison.