Personally if I went again, I would stay in Provincetown....albeit you would need to be a bit open minded to enjoy it. There is a restaraunt there called Front Street that was one of the best meals I have ever had. The rack of lamb was awesome and they had the best creme brulee I have ever tasted.
I stayed at
http://www.newseabury.com/accommodations.html
and it was also great. It is marketed as a golf resort, but I don't golf and loved it. It is just really layed back and relaxing in the fall.