Long haul airliners should have at least 3 pilots. 1 to pilot, 1 co pilot to call heading speed and altitude, and one other guy who can use google if something goes wrong. It is imperative that the flight attendents do not interfere with the crews handling of the plane.
A fourth man can handle radio operations and pack the bowl for the bong, again, do not let the flight attendants on the flight deck during the smoke sesh.