I believe key is to have one coordinator and to get the early ranks completed right off. With a little planning, and only a few members participating, they should go rapidly.
One person collects and calls out progress to the others. It has to be someone who has available time when missions start. Primary missions need constant updating. The first hour or so one person is strictly calling out updates to the alliance. Then, missions need updates every 15 minutes or so for the first day. Someone needs to inform the members what is required/left to do on missions. You don’t want everyone tossing darts when you need drops spun, and vice versa.
For Exploration: Primary rank does not take much. Spinning what is right around a few members and darting a few creatures is all it takes. Plan ahead and make sure that your drops are active and able to be spun. This is a great time to use those 5-minute scents.
Rank 1 long mission for us is spinning drops: 500. We have one member who heads out and is dedicated to just spinning. The other members can do the darting and finish about the same time. The coordinator calls out when each mission is completed so you do not have members tossing tons of darts when only Drops spun remains. Save those darts for the next Rank.
That leaves the alliance at Rank 2 Explore within a few hours, tops.
Best advice is to have members concentrate on the missions that hold you back. If you always have one mission holding up progress, dedicate a few members to concentrating on that. Or have all members put a little more time in doing that particular mission. Are drops holding things up? Perhaps the commuters can take side roads and spin on their way home. Darts holding you up? Perhaps those commuters can take some side streets and dart everything they come across.
We do not have to press hard all week. Monday is about the only day we have to really coordinate and work together. Then, Tuesday evening as we complete ranks. We usually have to concentrate of darts/direct hits/DBI or something. The rest of the week takes care of itself through just playing. It is getting that strong start that really helps.