With all of the the theories out there about what factions may or may not be in H6, I would really like to see each and every faction be playable in H6 with their own unlockable gear styles via commedations.
Obviously you have your Spartans and hopefully the Sangheli again, but I want more. I want the Soldier. I want the Brutes. Maybe ODST/Marine. Hell, I want the Flood! Obviously only if the respective faction is in H6.
Halo 4 did a decent job with the infected being altered with visuals, sounds, speed etc. I would like it to be directly influenced more from the Flood. Each faction of the Flood. Say your main as a Brute, when you play infection gametypes, you are a Brute in Flood form.
Each and every faction deserves their own gear with individual add ons. Add ons not via Req packages but only through unlockable commedations or via an experience currency. Much more inline with how Reach and H4 were. Not anything like H5.
Additional to a very large gear assembly, it would be awesome to have each individual gear such as chest, helmet, shoulders etc to have their own customizable color palette. As in a much larger palette than we have ever seen.
All of this would add such a huge replayability to multiplayer gametypes. All of this is something that H5 really fell short on and part of the game that just felt rushed and thrown together last minute. I am hoping they can achieve something of this caliber. If they can it would be pinnacle!
Feel free to use any one of the three H6 wishlists in my signature.