We have stayed at Cape Cod Camping Resort a couple of times and like it. We also stayed once at Peters Pond, Never Again. They sell out sites and have the transient sites scattered about. The guy at the end of the road, couldn't stand us "rvers". He thought he owned the place blocked the road all the time. A real problem.
We looked at Atlantic oaks and would stay there. Bring your bikes as they have a rail trail you can bike to different villages. We also did the whale watch out of P Town which as exciting and went wondering through Falmouth & Woods Hole on the other. For a day trip we went to Martha's Vineyard from Woods Hole ferry also a lot of fun. We went back 3x as you just cant do it all in a week much less a weekend.
Happy Trails