Re-balancing of weapons in each class... so there isn't just one apex weapon in each class. Ex. P416 is leagues ahead of M4, G36, Ctar, F2000... you should be able to use the weapon that you like without feeling like you're missing out on damage.

Option for those who want it to carry only 1 main weapon + sidearm... but can carry double/triple ammo.
Ex. I prefer to use my AR 99% of time but I can't because I run out of ammo and is forced to use 2nd weapon out of need... not because I want to.

Specializations: add improved dmg for each weapon class to each specialization... or at least just make it improved weapon dmg instead wep classes.
Ex. I would like to use be grenadier but then I miss out on 15% AR dmg. And smg are pea-shooters and I rarely use shotguns.

Increased shared stash size would be nice

Solo only (so it can't be farmed and exploited by groups/clans) :
Bounty on your head after ex. X kills without dying or X controlpoints under your control ex. all controlpoints in a neighborhood... npc factions send hunting/ambush parties after you in the open world (not visible on map, so you have to improvise or flee when they find you).
Rewards for killing them... gets tougher with each bounty lvl survived... increasing rewards with each bounty survived.

Improved friendly npc leader ai during controlpoints... or at least make them a bit tougher especially with lvl 4's.

Unique exotics and not just variations of existing weapons with different paintjobs...

Ex. of some I personally would like to see...
AR - Enfield L85A1
AR or Smg class MP40
AR - MP44
AR - SR3M
Smg - Scorpion EVO 3
Sniper - MK14
AR or Rifle - R4