Over-analyzed, IMO. Go back to basics, and stay there. If you're concerned with body armor, practice body armor drills. For those who wear soft body armor, be very careful with this. Historically, many/most (depending on the statistics you accept) cops/carriers are killed with their own weapon. If you gear up to defeat armor, you may defeat your own.
Staggering rounds is a premeditation to an anticipated outcome. Nothing EVER works out as planned. Count on that. There is no one-size-fits-all weapon system, so we must gear up according to what we may encounter. Planning on a specific condition will almost always ensure you will never encounter it. Like Opie 1, I'm a career professional (except I'm retired, and my wife only wears a bath robe). Accepted, established and practiced policies are carefully developed. Varying from them opens you to less than acceptable liabilities. If you are a civilian carrier, the [legal] weapon system doesn't matter. You will be a suspect from the moment you break leather. A good shoot will be a good shoot, regardless of the events or equipment. If you are justified to drop the hammer on a person (whether you actually do or not, hit or miss), nothing else matters. Ride out the process, and stick to your guns. I've seen many careers end badly because a good officer allowed himself to second guess his actions in court. The same applies to civilians. If you are confident in your thought process and actions, the investigator, prosecutor, judge and/or jury will feel that, as well. If you carry, have handy your credentials, and find a GOOD lawyer, specialized in such cases, before you need one. If you find yourself in a situation allowing you limited phone calls, the lawyer should be the first. If you are read your rights, invoke them, immediately, and wait for your mouthpiece. Volunteer nothing, and make NO spontaneous statements. Anything you say WILL be used against you.
Life is tough. It's tougher if you're stupid. -- The Duke