Do want:
The Arbiter
Playable Elites
ODSTs
Duel wielding
Armor that isnt fugly
Equipment to make a return as well as armor abilities and everything else
For the love of god bring back every weapon, vehicle, ability, equipment, whatever that has ever been in the series and then taken out most notibly unsc flying vehicles!
Better female characters
More gore, darker tone.
More chunkier, grittier multiplayer armor/colors.
Martin O'Donnell.
Explination as to why chiefs armor has changed.
Brutes
Drones
Skirmishers
Some sort of night vision
Dont want:
Only bright colors available for customization
Bad dialoge (looking at you spartan ops)
Cortanas resurrection.
Sights or weapon attachments (at least not in multiplayer)