Clan tags
Multiplayer lobbies + quickplay

1. Clan tags would be useless without the still not implemented clan support

2. The need for lobbies has already been brought up.

3. Quickplay? How in Sam Hell do you propose doing that?

New weapons and maps: taking more creativity with the weapons to make some more original weapons, that are semi-based on reality. (Like the Hjammerdein and Freakin' or whatever it's named. Some bigger less choke-pointy happy maps could be cool, more expansive routes for the parkour)

More story for the campaign missions. The brief bits are alright, but the two new DLC maps seem to ignore the continuity with the Security guys who were always there, and the fact Resistance had already tried to blow up the tower once. (You think Security would have been tighter around the place.)

Branching abilities. (Instead of just Hack Turret, you could choose sabotage turret. Instead of Lazarus Grenade, Poisonous grenade and so forth. )