keep everyone out of each other's way.

Create the main cooking area in a place where no other traffic patterns will intersect with it.  This would mean that the cook should have a fairly compact work zone comprising of the range, prep sink, and refrigerator/freezer.  If the refrigerator/freezer is a bit too far away or will be frequented by others during meal preparations, then adding refrigerator drawers near the prep sink can be a great help.  Items frequently needed during meal prep and cooking can be kept here, such as milk, butter, eggs, and fresh vegetables.