That's a pretty good lineup and comparison. I own a 303 British (Enfield Mark 4 No 1), 243 Win, 9mm and 22LR of course. I have shot all but the 6mm and the 50 cal.

You're right about how complex this subject is. I can tell your expertise is much better than mine but I occasionally spend some time reading ballistics charts and stuff like that. There is a book that I have and really enjoy called Deer Rifles & Cartridges by Wayne Van Zwoll, PH.D. Have you read that one by chance?