I think anything Cooper and Keith had to say about handgun design and carry, bullet weight, caliber and velocity, and fight-stopping power would be interesting and informative. Jeff Cooper's commentaries, which he continued to write until his death in 2006, are available online. They are filled with gems and he was very aware of the then-latest in handgun invention and bullet design, which includes most of what we have now. Just as an example, cruise through his comments on the development of the 10mm and its subsequent incarnation in the .40 S&W.
You would do us all a great service if you would reduce the best correspondence to, for example, a blog or a long post on this forum. If you need help transcribing, I'll bet there would be volunteers.