IMHO, planning was the key to making our recent trip successful and enjoyable for all. We just returned Sunday, and were able to do all four parks, have afternoon breaks, and not have any meltdowns. My kids are 7 and 3, so we had to not tax them too physically because it was hot. We were at the gates 1/2 hour before opening, so we could get to our first attractions easily. For instance, in MK, we proceeded right the Fantasyland to ride Dumbo, Peter Pan, Pooh, Small World and Teacups before any crowds. If the stand-by line is less than a 15 minute wait, don't waste a fast-pass on that ride. In most cases, you can't get another fastpass until you use the one currently in your possesion. Also, rider swap was great for us, my son could ride all the 40" and above rides twice, and the rider swap pass does not have a time on it so we returned at our leisure, sometimes after our swimming break. As for meals, we had a PS at 8:00 am on our first day at AK. The breakfast was nice and we were already well inside the park, in Dinoland which is perfect for little kids, before the rest of the crowds were there. I planned our trip for last week, partly because I knew the crowds would be less, and we took our 1st grader out of school for 3 days. We never waited more than 20 minutes for any ride. It was perfect.
My husband is a big planner too. We printed out touring plans, which helped us become familiar with the flow of rides in each land. We followed them to some degree, allowing for character stops. Because we arrived early each day, by 2-3 pm we could take a break and go back to hotel for swimming and early dinner, then come back to the parks for the evening. BTW, I agree with the "best days" philosophy of the touring plans, which say you should visit a park the day after EMH.
We rented a car which allowed us so much flexibility and actually ended up paying for itself in the money we saved on souvenirs and food. We made a pit stop at
Walmart after the plane landed, stocked up on bottled water, snacks, cereal, milk, etc. We also let the kids buy their souvenirs and squirt bottles there and they never asked for another think in the parks which totally amazed me. We requested a refrigerator in our hotel, and with the exception of our character breakfast, we had breakfast in our room, ate wraps and snacks for late-lunch and dinner and took loads of fruit, water and snacks into the parks each day. It was hot, so no one was really that hungry -- infact I had to force food on the kids during the day and remind them to drink water.
After we put the kids in bed, DH and I would review for the next day and come up with a starting plan. I enjoyed all the planning, and looked at it as helping my kids have the best possible time. DH was reluctant to go because he had heard so many horror stories of 2 hour waiting times and crying kids. It was an accomplishment that it all came off without a hitch.
Hope this helps...enjoy the planning and enjoy the actual time there even more!