Sorry, forgot to answer your questions. I was so excited to have you join in our meet thread.
Most of the cabin categories are in gty status, which means that most of the rooms are sold out and they are going to play musical cabins with whomever they can get in the remaining few months. If you decide to change cabin categories now, you will not be guaranteed to even be located near each other. I don't think that would be acceptable to you as your kids are younger.
The way the ship is designed, each cabin is near some public rooms and farther from others. If you are near the kids clubs, you are far from Topsiders. If you are near the Mickey pool, you are farther from the kids clubs. The ship isn't that big and believe me, after a few meals, you are going to want to do some walking
We took the same cruise last year and it was wonderful. Expect sailaway to be chilly and bring jackets for the kids. Once you wake up on Sunday, it will be warm and sunny and in the 80's.
The superbowl will be shown on the ship in all of the lounges and on the deck 9 jumbo screen. Formal night will be moved to Monday.
Your kids are the ideal age for this trip. My kids were 7 and 9 on our first cruise. They are 11 and 13 now and this is still their favorite vacation. They are not interested in the parks anymore. If you have any more questions, ask away!