I did several long rides before as a "team" . Some were OK, some were disastrous, because the riders could not agree on the speed and rest/feed time.
I would suggest talking to your riders beforehand and discussing the strategy. If you want to go as fast as possible all riders should work in a pace-line as long as possible. Although on a 200m ride the fatigue may set in and it will be hard to keep the pace-line. If it is just a sight seeing route, pace-line is not important. .
I would also suggest choosing a ride captain that will decide how to ride, especially when the fatigue set in.