saving money on food is something that we work on every visit because we never find free dining to work economically for us. RO discounts work much better in our experience.
We like to eat breakfast "on the run' while we get ready in the morning. We have small boxes of cereal, peanut butter, a loaf of bread, milk and fruit in the room and make breakfast from that.
Then we eat a large buffet lunch midday when the parks are busiest, followed by a rst/swim at the resort. Then it's back to the parks where we pick up an inexpensive dinner at counter service, or snacks as we stroll around world showcase in Epcot.
We do sometimes have one day with a character breakfast and a fancy sit down dinner with little or no lunch. Only drink water, don't waste money buying drinks and you bwill save $$$ as well. Buy or brink a water bottle and fill up at fountains or as for water at counter service and fill bottle from that.
If you really need a soft drink, you can get free sample ones (small cups though) in Epcot. perhaps not typical ones for North America, but we like them. Yes, even Beverly!
If your fridge is working you can get Garden grocer or WeGoShop to deliver some grocery/snack items to your hotel.
Enjoy you experience! I am so jealous about the Cinderella Castle suite! I would love to stay there someday!!