The only parts of your response I need to reply to (most of it is completely true, btw) are 1) when a person I have shot is moving do do ANYTHING but put his hands in the air where I can see them, then by God that is a threat because if he has them under his body to drag it along then my assumption is that he has a gun under there. 2) the only thing I am going to tell an investigating officer or DA is “he did xxxxxx to convince me that he was a threat to life/safety and so I discharged my weapon into him to eliminate that threat..... I do not wish to make any other statements without my attorney present.” If I have to repeat that 175 times, I will.
For your sake, and respectfully, I strongly suggest you seek the advice of an attorney admitted to practice in your jurisdiction before you reach any conclusion regarding the use of a firearm.