We got back 2 weeks ago from a week-long trip with DD6, who still loves to see the characters. 5 of our 7 TS meals were late breakfast character buffets. They were all good. Our meal plan worked out like this - snack breakfast in the room (fruit, cereal bar), character buffet around 10:30am (gives you enough time to get to the parks, do a ride, grab a FastPass before eating), snack around 2pm and cs dinner around 6pm. Besides using the snack credits for pretzels and ice cream, we also had fruit the buffet servers let us take from the buffet to save for later.
At that age, the meals are definately all about the kids. Enjoy.