Nothing to do with your route but Dennis Hill used to coordinate a group he called loosey goosey. They would pick a destination for the next travel day. Some would get up early and arrive early. Some would sleep late and arrive late. Most were somewhere in between. But, they all knew who was still missing until the last of them arrived.
When I was a kid, my family traveled with other camping families. Our system was that the leader would drive for an hour then stop to watch as each family passed making for a new leader who continued that pattern. That way, if anyone got in trouble they were never too far back for someone to go help.
Linda Sand