Besides distance between the pedals, there is also the heights of the pedals to consider. Brake pedals are usually 'higher' than accelerator pedals - in the Model 3 it is about 2 inches higher . I don't know what the specific reason for that design is, or what the industry average is, but I think its plausible that changes in that distance differential would have an effect on reaction times, odds of misapplication, and overall safety with regard to pedal application. Also pedal lengths/widths, materials, texture, tension, travel, and location of fulcrum probably have an impact. So, there are lots of places to look for faults and/or improvements.