Ponder this one extra option...
You could try to rent TWO Fort Wilderness cabins.
A week's stay, in a 2 BR unit, during the holidays, at OKW (the least expensive on-site DVC resort), is 405 points. Most people seem to rent their points for 11 dollars a point, especially during peak seasons. So 405 points will run you $4455.
Saratoga Springs would be 415 points. $4565
Boardwalk Standard View, 426 points. $4686
Beach Club, Wilderness Lodge & Boardwalk Preferred View, 462 points $5082
Each Fort Wilderness cabin costs $349 a night during the holiday season. So for 7 nights, that would run $4886. Granted, in these rooms you will have to add sales & resort tax, which would put you at around $5450. But you could also, theoretically, add one to three more adults in to your party (as the cabins each sleep 6, and you have 9 in your party). Even if you didn't add anyone else, the difference in price would run each adult anywhere from $150 to less than $70 a person. For a 7 night stay, that's only between 10 & 21 dollars a night. Make some use out of the kitchens in the cabins, even just for most breakfasts, & maybe sacrifice a souvenier or two, and that difference could possibly be made up. Plus, you would be in one of the more interesting areas of WDW, with a lot of unique amenities, the campfires, the outdoor movies, the pony rides for the kids, petting zoos, launches to the Magic Kingdom, and one of the best meal-deals in all of WDW, with the Trails' End buffet costing only 18 bucks per adult. Something else to ponder is all.