I vote for Crystal Palace. I think the last seating for breakfast is about 10:30 am. I know this is a little earlier then you wanted, but this really is the best time to goto Crystal Palace. First, breakfast is cheaper then lunch. Second, Disney knows how to do a breakfast buffet. I like lunch and dinner buffets at Disney too, but nothing beats their breakfasts.
Third, and most importantly, the place starts to clear out at about 10:45. You get so much more character interaction when you book a 10:30 breakfast, compared to a 9:00 am breakfast. They don't start seating for lunch until just about everyone eating breakfast is out. Imagine sharing the characters with 10 tables for the last 20 minutes of your meal, as compared to the normal 100 tables. ITS GREAT.
I'll be at Crystal Palace in 17 days for my late breakfast, and I can't wait.
PS. Also consider an 11 am breakfast at Chef Mickeys. A short ride on the monorail, and for the same reasons as stated above, you will have the characters practically to yourself. Chef Mickey's doesn't serve lunch, so no rush to leave either.