I will agree with those posters who suggest BOG lunch on a MK day. It is only one CS credit, and you still get to eat in the castle. It is also pretty darn good food, and a nice break. I don't see Epcot on your plan, so Akershus is out. If you cannot get CRT, and I bet you can, I would look at 1900 Park Fare at the Grand Floridian. The Stepsisters are hysterical, and it is only one TS credit. Your son will have fun there as well, and Cindy and her Prince pop in to dance. IMO, this is one of the best family Character meals because it does not center on girls.
I think Tusker House in AK is a really good choice on Animal kingdom day. The food is good, and you could plan it late so you do not lose time in the park. There are good CS options in that park, so you would be all set for the day.
I love the idea of resort hopping on your down day. If you can book 'Ohana that night, check out the time Wishes id scheduled. You can have dinner, and then watch it from teh Poly Beach. There is also a cute little Electric Parade on the Lake every night. I love that parade, it was the only night time entertainment when I first went to Disney. My husband actually booked our room at the Contemporary so that the kids could watch it when they were little.
If you manage all your ADR's and are not opposed to one OOP meal, think about a breakfast. 'Ohana at teh Poly has Lilo and Stitch, and is a reasonable price for a nice character breakfast. You could take the bus to the MK, hop on the monorail and explore the monorail resorts, schedule a late breakfast at the Poly, and then skip over to the Epcot resorts. The whole Boadwalk area is a nice place to visit. You can check out all of the resorts in that area, and then head back to your resort to relax and swim. From there you can have a later dinner anywhere you like.