Very spot on review regarding the effectiveness of the 9's, 45's and the .40's......tough for many to accept the order in which you listed their effectiveness. The ballistics are indisputable, as are the many records compiled by those who are paid to closely monitor such activities, of which you made mention.
As to the original question...not sure where I'd draw the line as to a minimum, but I carry a 629 4in. with handloads consisting of 300gr. WFNHC's with a MV of 1,250 fps. This way, concerning myself with the "is this enough gun" question doesn't take up the precious few moments I might need to act accordingly.
