High volume of return fire is essential in almost every scenario. Your attacker may respond and change directions, be fluid and bail out the opposite direction they go. Remember your rounds will go through and out in the same way theirs comes in creating the same shrapnel as bullets fragment so your pistol might turn into a mini shotgun.
Dropping to the ground and shooting feet from underneath a vehicle is also valid if the angles and positions give you concealment. All very dynamic and fluid and endless what-ifs, have options in your head, and have a double stack with an extra mag.