I agree with standardizing on a single system. At one point I was carrying either Sig P series or various makes of 1911's. Knowing that eventually my youngest is going to start shooting ( and probably get his CHL when of age) and that my wife is not particularly fond of shooting, I figured it would be easier for everyone if I standardized on a single platform. Now my the wife knows how to make ready and render safe (and strip and clean) all of my carry pistols, and how to safely handle them in my absence.
A bonus to this is the commonality of parts and accessories.