My personal takeaway: I would look long and hard at Saratoga Springs, maybe in the Congress Park area if you want to splurge on Preferred View points.
The rooms are all newly renovated. There are two feature pools and three leisure pools, a golf course, quick service and table service dining, bicycle rentals, community hall, pool games, etc. Disney Springs is walking distance with dozens of shops and other places to eat.
It may not have the "wow" factor of BoardWalk area or grand Floridian to a frequent guest, but I cannot imagine anyone being disappointed in a balcony view of Disney Springs from CP. It's also one of the cheapest
DVC locations.
Personally, I would not even consider asking 18 people to commit to the hassles of a split stay.