-More weapons.
-Less recoil.
If you had those two things, the game would be more competitive and there would be no need for an Aim Enhance module.
I love the game as-is, but if there was more diversity in weaponry, I think the game would become more dimensional. You may think I'm a noob, or something, but if there was less recoil for weapons, it would definitely have more of a futuristic effect and it would become a battle of aiming, not of spray and pray.
I have no complaints, only suggestions. Much love, Crytek.