As has been stated, the mission dictates the equipment and the tactics. You do not lose enough from a 357 mag going from 4" to 2 1/2" to worry about. You will get more variation in velocity gun for gun usually. A 125 grain JHP is still doing 1350 from a 1 7/8" 357 Magnum and a 145 STHP does 1250, not much of a trade off. Different loads in different cartridges are affected differently due to burn characteristics of individual powders.
Carry what you shoot well and are comfortable with and don't sweat the tiny details.
My rifle and pistol are tools, I am the weapon.