Our favorite counter service places that are included on the dining plan are Tuskers and Flame Tree (both at AK) and we like Cosmic Rays at the MK. We also like the Sunshine Season Food Fair at the Land in Epcot, but I believe it will be closed during your visit. Another excellent value for a counter service meal is the Pepper Market at the Coronado Springs Resort...it has a HUGE selection (everything from tacos and sandwiches to prime rib and anything you select would be included).
I think you have made good choices for your sit down meals.... personally I would opt for Citricos or the Yactsman Steak house over Narcoosees for a prime dining selection (you have to use 2 sit down meal credits per person to eat there) Citricos is also at the GF and it gets consistently better reviews than Narcoossees...and my one experience at each led me to believe the reviews....Narcooses wasn't bad....just not great.
I think Boma's is the best buffet on property....yum....can't go wrong there.
Lots of people love Liberty Tree Tavern....I am pretty ho-hum about the place....great character interaction, but we have found the food at Crystal Palace to be much more interesting (although it can get pretty loud there)
Other great sit downs on the dining plan (1 credit per person) are Spoodles and Kona Cafe at the Polynesian if you like seafood/mediterranean/pacific rim....they are both excellent and very nice calm places to dine.
I really like the Concourse Steak house....we have never had a bad meal there and have always had great service....although I have read about others that did not share that opinion.
