My first suggestion is:
Add more Loadout Presets ( Could be unlockable with GP or Chips ) Basically make the Presets 5 in total.
I think most players would agree that only 3 loadouts is nowhere near enough, i myself use 1 for sniper, 1 for Scar and the last one is a normal assault rifle.. i can't have an SMG or LMG.
Second Suggestion is:
Make it so we can add attachments to secondaries, i think lasers and sights would be good enough.
Third Suggestion is:
Make it so we can unlock a skin for our weapons every 10 levels or so, as the gun level cap is a 100 levels, we would have 10 skins for a gun if we max it, or depending on how many levels you choose to make us get a new skin.
Capture the flag mode, we all know the good old capture the flag mode from many different titles, each team has their own flag and they have to grab their enemy's flag and get it back to their base.
Pretty simple yet very fun and challenging and needs a lot of strategical planning.
Thanks to the Devs and Fellow soldiers for reading.
Have A Nice Day.