Now, one of the things that this game doesn't have is a sprint button. Since players each have their own set speeds, do you think it's necessary to add a run button? I'm not really sure if it'll have any repercussions, but hey, maybe anyone else can think of one.
The way the game is set up currently?
No, the game would not benefit from running, it would probably suffer from having it included.
They would have to change somethings up before adding such a feature. Maybe in a future installment.
Instead of running, we just have a bunch of golden shoes that makes you faster!
Then again, not being able to sprint makes the characters different and matches your attributes. You can't expect a tank like Big Daddy to win a race against small PaRappa.