Like for example how the NPCs are able to use cover based shooting mechanics akin to what you would see in Uncharted, Max Payne or Gears of War.
The animations are already there and you can see that NPCs are able to blind fire from behind cover.
What would it take to assign a contextual button prompt from behind cover to "enter cover fire mode".
Someone should really make different third person reticules based on what type of gun is being used while adding some aim assist or a bigger hit box. You wouldn't believe how many times the tiny dot can be on an enemy's head 10 feet away and still miss.