Love your rules - very similar to what we tried to stick to when we had the dining plan a few years ago. One breakfast that we used the dining plan for was a lazy day when we didn't go to rope drop anywhere. We had a late breakfast at WPE in Downtown Disney. We split a few breakfast pizzas between the four of us before we hit DQ. The pizzas are really big enough for two, and at the time came with one or two sides and a drink.
We also got the cookie or krispie Mickey for dessert when offered to save for the kids. Then for the kid's meal, we would get the fries & fruit instead of fruit and cookie. DH and I never ate the CS desserts. There were too many other snacks to try throughout the day; and we usually split a dessert at our TS and let the kids eat the other dessert. The kids' TS desserts are pretty lame. This saved us from buying smaller items using the snack credits for the most part. We usually bought smoothies with the snack credit or a larger snack that we would all eat a bit off. That way we got to try about everything!