I don't know, maybe the opposite would be better in this game. Nerfing your movement speed and making you press a button or anything to get it back to "normal" would suck for longtime players. However, a walk option wouldn't be without it's uses. I mean for one, it would be great move slower when trying not to fall off a block. Two, in theory it could provide a combat advantage if implemented in a way that changes your stats. Running into someone's fist or sword or claws would result in them hurting you worse in theory, while your own attacks would have more momentum when moving at full speed. So by increasing defense and reducing attack while "walking", you can create more intricate combat. And third, and probably useless for most people, I think it would add a nice touch when it comes to RPG maps to be able to choose to not always be running at full speed wherever you go. I just think that instead of lowering the normal speed of our players we can give an advantage to going slower once in awhile.