Recoil - we need more recoil on all the guns, different recoil on each gun will give said guns individuality.
Gun Class Distinction - at the moment smg's are all range weapons, they need to have their damage dropoff reduced and spread increased, but the high rate of fire will make them good at close quarters.
Assault rifles need a lower rate of fire a longer damage drop off than smg's tighter spread etc, to make the them suitable for medium to long range firefights.
Maps - Do not take any advice from IW on map design, they failed miserably on MW3.
Aim Assist - it's currently too strong, lets make this game a competition again.
Connectivity - you got this badly wrong in Blk Op's, MW3 was even worse, this has to be a priority.
Some kind of beta, the last couple of COD's have suffered from a proper beta, played over the interweb, sure we will all see some of the game before release, but after the last COD I can assure you I will not buy this one until I have tried it so it has to be good.
P.S. War was an amazing gamemode, much better than kill confirmed, why was it binned?
EDIT: the killstreaks need a complete overhaul, they a rubbish as it stands and overpowered!
Also the perk system is stale, you and IW have flogged that horse to death, surprise us with something better!
Something like that but make the animation and recovery time faster. The stabbing animation is really cool in BF3. In BF3, you stab your enemy's throat, maybe they can just slit your enemy's throat in BO2 and make your enemy have a panic animation before dying.