Hi Laura,
Great planning! I always book our Advanced Dining Reservations at 180 days out too. I must say that
Boma - Flavors of Africa is a "must-do" for our family on every trip. To minimize the travel time, we always have dinner at Boma on our Animal Kingdom Park day. You'll be in that "part of the World" anyway. After dinner, we will often grab a cab back to our Resort for under $20. This is because the buses don't travel directly from Resort to Resort). Otherwise, we head to Downtown Disney for awhile and switch buses at that point.
Likewise, you'll want to plan on dinner at
Whispering Canyon Cafe on a Magic Kingdom day. You'll simply walk out the front gates, hop on a ferry over to Fort Wilderness and then go back to the Magic Kingdom for the evening parade and fireworks. The antics and entertainment at Whispering Canyon make this restaurant a lot of fun, and the boat ride is a relaxing change of pace.
Maya Grill is the only one of the restaurants that you mentioned which I might reconsider. However, you could always hop on a Coronado Springs bus from any Park to head there for dinner. It's getting back to your Resort after dinner from there that will leave you in the same situation that I mentioned above with Boma.
Many of my favorite restaurants on property can be found inside the various Resorts, so I'm happy to see that you are considering some of those. Transportation is definitely do-able without taking up too much of your day, as long as you plan the right Park to correspond with the restaurant which is closest to it on your list.
Have a wonderful vacation,
Kaylene