It's worth remembering there is a very established swap culture on the 747 especially. All done by contacting the pilots by email or text and suggesting a deal.
Commuters are keen to 'back to back' trips, so as long as the legal rest limits are observed, they will swap so it gives them 5 or 6 days off together.
Everyone likes different things, so it would be easy to swap similar credit trips. If you liked the west coast of the US as opposed to going East, there are many options to create a roster more to your taste.