For us - No way for the double beds. Have to be well rested to enjoy our stay and do not want to be tripping over one another or an airmattress for that long. I would cut a few days off and upgrade. It is essential that the pool for my kids comes first. They would rather cut a few and have a slide to play on.
I have been cutting groceries and stocking up on Disney gift cards too. When I can I buy a 25.00 one and add it to my collection. On Valentines dat, my DH got me a Disney gift card, lol. That is all I ask for for birthday and Christmas. The kids get them too and it covers all their snacks plus they learn to budget. I have been doing this since they were 10, 7, and 5.
Whatever you decide will work because only you know your family.
You will be in Disney and how you decide to do it to make it great is up to you.
Best of luck!!