Shooting to wound versus shooting to kill is really a different issue from whether the use of a weapon is justifiable.
True, but you brought it up.
A firearm is, by definition, lethal force (it is capable, and indeed likely to cause serious bodily harm or death if used), whether used to shoot a gun out of the bad guy's hand a la TV Westerns or to place two round center mass, and one between the eyes. As a strong general rule, a plan to intentionally shoot to wound disregards a whole lot of what goes on in a lethal force encounter.
I would think a plan to always intentionally shoot to kill does too, and especially in your subsequent encounter with the law.
Very experience SWAT or similar tactical operators may be be able to do it. A sniper at a remove, in the right circumstances, might do it. But the "average" officer or civilian gun-toter? Probably not, not intentionally. You did address dealing what to do if the wound is insufficient to stop the threat, but you're still disregarding what we know tends to happen in a violent encounter.
You are correct as to reports of encounters of LEO in at least their first gun fight. However, I believe it to be a matter of training. LEO don't get enough of it. But MA do get lots of training, albeit not usually on using guns as opposed to defending against guns. But IMHO, no one should be carrying/intending to use a gun unless they get lots of proper training.
Are there circumstances where it is possible and even desirable to shoot to wound? Yes. But they're few and far between.
I don't agree, especially if the gun-toter gets sufficient training.
And we haven't even talked about the mental problems a shooter may have after killing someone. They are real and significant, even for those who shoot and only wound. Killing is usually worse. That should be part of any training; dealing with the aftermath of any shooting.