Sometimes changing weapons quickly is necessary, so hitting numbers is just too clunky imo. I hate FPS games where you change with the numbers. Pressing shift is right by your finger and is the most commonly used, and most people are used to it. Did anyone watch the Bannerlord livestream? Their combat looked pretty interesting, however it's not really different from Warbands ideas, just vastly improved animations. I'm really looking forward to the multiplayer on that.
I am assuming you meant Shift for sprinting?
Well, if you have a big map and need to get from point A to point B quickly, but without your stamina draining 5 times in the proccess, adjustable levels of running speed would be really cool. I'm basically suggesting a mechanic, that would add 5 running speeds for various distance running and you bicker about the controls. It could as well be bound to + and - we are in 2016, rebindable keys are a certainty.
So, that means, you're playing a game at being a cunt and disagreeing with everything I say, out of spite.