You'd want the speed skill for that. However, that would realistically only affect them running back to 0,0 after construction is done as otherwise they have to be in your party and so will move at your speed - and most people would just hop into a ship/vehicle and drive off to the next construction point.
Instead of opening a new thread, can i just ask here if the race of the NPC builder makes a huge difference to build times? I have noticed that some are a lot quicker than others but is it down to race? Or is it purely random?