In reading a contract with a large liveaboard fleet recently I noticed something interesting...
It basically said that if the boat was booked as a discounted group trip, that the group must have an appointed and identified leader, that the boat would only deal with that leader regarding issues, complaints, communication, etc, and that leader must have decision-making authority over the group.
So while you may not have considered yourself the leader, it's possible that the boat may have.
That's fine. However, none of that came up. The only "leadership" done was forwarding the payments en masse, no big deal.
I did not have to arrange anything else other than: "What date are we going?"; "Payment due this week"; and, "Do we want a group t-shirt?"
Far cry from organizing flights, ground transport, insurance, waivers, certifications, teaching classes, land tours, restaurants, hotels, dealing with individual "issues", etc. These were all adults and dive professionals who got on the island on the flights they booked, met at Splashers at the appointed time, got on the boat at the appointed time, dived their brains out, and left the island on flights they booked...all with no hand holding or "what do we do now?" concerns.