Boma is very good; great food, great location. It would also give you the opportunity to wander around AKL which is one of the most serene places in Disney.
Chef Mickeys breakfast is a good character meal. One tip is to book one of the last spots for breakfast and use it as a kind of early lunch. This way you can get in MK early, do some rides/shows and then have a break approx 11am before hitting the park again in the afternoon.
Others that are in parks and not hotel resorts that you might want to try:
The Princess breakfast in the castle is nice with great characters and it is 'the castle'.
The Crystal Palace buffet with Pooh and friends is one of the best quality buffets and of course characters.
MGM Sci-Fi Diner is a nice quirky place to eat being themed like a 50s drive in cinema, standard fare but great theming.
And for a totally different experience you have to try Prime Time in MGM for one of the most unique dining experiences you will encounter.
Loads more to try, so making my list for December :-)
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