Great diagram. I designed the placement of my rack around the location of my bulkheads so that when tied down the straps go around the boat very close to the bulkheads, the concept being that the boat will not flex very much at those points.

Regarding the stern overhang. It may sort of depend on the highway regulations in your jurisdiction. Here in BC I think you are allowed up to 3' overhang before you have to hang a red flag off of your merchandise. Sort of like taking lumber home from the lumber yard. Either way mine overhangs ~4' and I have never been pulled over.

Conversely the extra bow overhang allows you to see your boat while driving letting you know it is still there while you boogie down the highway

grant