I'm sure you can find some nice meals off site. However, they don't do you much good when you are in Epcot for the evening and want to have a nice meal, or desire to eat on the shores of the Seven Seas Lagoon with a view of Cindarella Castle as you watch the MK fireworks. We actually think there are quite a few good WDW restaurants, and by the NY standards we are used to they aren't prohibitively expensive. The dining plan can make them a good deal.
We have the TIW card and have never had difficulty using it. Haven't been one place where they haven't accepted it, including numerous character meals at 1900 Park Fare, Cape May Cafe, Norway Storybook Princess.........