I no longer brake-check tailgaters. I figure they are mad enough already, no need for me to escalate the situation.

As far as drawing on someone who gets out of their car - Absolutely.
If I was standing on the sidewalk, and someone was coming at me in a rage, I would most certainly draw on them; no different if I'm in my car.

They can yell and scream all they want from inside their vehicle, but as soon as they approach, all bets are off, and I am prepared to defend myself and end the confrontation as quickly as possible.