First take a deep breath. You just need to look at things from a realistic perspective. I've done this before and it's not as difficult as it sounds. I've taken group trips to WDW personally and had clients who took group trips....it's much easier on everyone involved if everyone knows there will be a certain amount of individual time.
It sounds like you are a planner and if so you will be utterly frustrated with those in your group who are too laid back to plan. You should plan a few meals together, plan an activity or two, and then let everyone do their own thing. It will save your sanity and give everyone enough time away from each other to really enjoy joining back up.
Maybe you want to reserve a Wishes cruise one evening or if there are children a fun Pirate Cruise morning. If there are any special events happening (like your anniversary....birthdays....etc) you could plan a special meal and order a cake to celebrate. With over 8 people you would be considered a Grand Gathering so there are a few extra cool opportunites you could take part in.
You should get together a sample of resorts, one from each category, so that your family has options. With Disney transportation, everyone could stay at a different resort and be just a bus ride away. If the WL is what you and your hubby want to make it a nice trip...then you should stay at the WL and not feel guilty about it.
You know that your ADRs need to be made at the 180 day mark. When you get closer to that date, I would put an email out there for people (call if they don't do email) and give them deadlines. "If you want to join us for this dinner on this night at this location let me know by this date". Send them a final email one week out and then those that responded will eat with you and those that didn't...well you just can't fret over it. It'll make you nuts.
Let the group know your itinerary. If they want to get up and be ready to leave when you are then GREAT! If not, let them use their cell phones to catch up with you later. They can hop on Disney transport and catch up when they are ready....no point in it ruining your trip while you wait on their schedule. Family/friend trips are great but you have to figure out what your boundaries are going to be because you are paying money to spend time at WDW.
You will have some incredible memories of your family together at WDW and that's just a priceless thing!!
