Campaign:
Skulls
Long campaign
Flood and arbiter to return
Multiplayer:
Casual and Competitive playlist, with displayed CSR.
NO Armor Abilities, unless they are used like power weapons.
NO Sprint, this encourages chasing and turns Halo into cat and mouse.
NO Ordinance, please god just no ordinance. This COMPLETELY ELIMINATES map control. It also bases the game off of luck.
Take out the waypoint that shows noobs where the power weapons are.
Infection, not Flood, Infection.
Needs more simple arena style 4v4 maps at launch.
Would be cool to bring back all the old gametypes plus new ones.
Forge:
Clean looking blocks, like Reach.
Toggle Dynamic Lighting.
Big, diverse forge map.
If they have all this I'll be happy with the game.