I can’t answer your questions about the rooms and check-in, but I can speak to tips about being the primary planner. I did a trip with 17 people last fall, I was the primary planner and it was definitely my least favorite trip. It felt like hearding cats all. day. every. day.
I would suggest setting up an itinerary (maybe even just as simple as ADR’s and FPP), and then let people stick with you the whole time, or just meet up for the ADR’s. They could even do the FPP on their own. I would also set some expectations for the group that sticks with me…
we’ll take bathroom breaks regularly, and it would be so great if everyone could TRY each time. (maybe explain the rationale for this also)
same with snacks… we’ll be stopping regularly, but let’s all try and stop together.
That type of thing.
I travel with my brother’s family regularly, and we are a group of 10, but we have a good rhythm, we seem to value the same things, and we seem to tour the parks in a similar style. We RD and fastwalk every day. We prioritize rides and whatever we have to do to wait in line the least amount of time. It’s easy with them, and I don’t mind being the facilitator/planner/leader in that scenario.
The trip that was 17 people included my sister and her family, and what made it difficult is that they had a very different style of traveling. They liked to stop and smell the roses a lot, needed quite a bit of warning if we were wrapping up a break or meal, and always had someone who needed to go to the bathroom right as we were leaving.
It was frustrating for everyone.
Also, MDE had a LOT of issues with me holding all the plans for 17 people. It glitched and crashed a lot, and I spent 3 hours at GS 3 different days trying to sort it out. MDE doesn’t seem to have a problem with my regular group of 10 though, so hopefully it’ll be seamless for your group of 9.