You as a CHL holder are at the same disadvantage as a Law Enforcement Officer. You can only respond to a deadly threat with deadly force. That means the Bad Guy gets to draw first, lunge first, swing first etc. All you can do is remain situationally aware, anticipate potential threats by giving them a wide path and train your muscle memory to repond before impact.
And yes, drawing your weapon without pulling the trigger is a use of deadly force.
The Bad Guy had to be threatening or attempting to use deadly force before you can do anything about it. You can't go through the parking garage at 9PM using a combat glide with your weapon drawn because somebody made something go bump in the night...
I can look very mean with my skull cap on after a long day at work heading to my vehicle, my wife was probably just yelling at me on the phone becuase I stayed at the office too late.
If we happen to be crossing paths in the parking garage I'd prefer it if you keep your gun in your pants.