Some people would say to only stay Sun through Friday and stay elsewhere on cash on Fri and Sat night because of the higher cost of points. But others of us would advise you to stay put to avoid that homeless feeling.
An AP is a good investment if you are going to schedule your trips to fall within one year's time. Then you can also purchase the Disney Dining Experience card to get 20% off on most table service, a few counter service and that includes alcohol if you choose to drink adult beverages.
There are those who will say to stay in a studio vs a one bedroom. They both sleep the same number of people and you use about half the points. But some of us like the luxury of the one bedroom.