My son and I (he was 9 at the time) did what you are planning to do in August 2001. It can be done; and we had a blast doing it!
Back then EE was for 1 1/2 hours. We did all of FL rides except IASW (was down) we did the race cars and Buzz. At @9:00; right after using FP for Pooh; we got in line behind a CM with a rope and walked BEHIND the CM to Splash Mountain. I got a FP for BTMRR (At that time I also had one for Peter Pan) We rode SM. Went back and did PP. After PP got line for the first raft to Tom Sawyer's Island. Had a ball exploring and looking for a paint brush; no luck.
Took the boat back over, got a FP for JC; used first FP for BTMRR, then did everything in AL except the treehouse and POTC. When we walked into AL, we stopped for my son to get a picture and autograph with Captian Hook and Peter Pan.
All of this was done before 12. At 12 went to Pecos Bills for lunch. Before getting in the LONG line to order lunch, I went to HM and got a FP. By the time we were done eating it was time to use our FP.
We left MK the day at about 1:30-2:00.
That was the only day we did EE at MK. We did the other rides during afternoon and evening visits and during e ride night.
I know most people think it's crazy to "run around" like that.
But we enjoy it. I don't think trying to do as much as you can is a mistake. The big mistake I made on our first trip was not getting park passes that would allow us to enter a major park each day. We were there for a week but had 5 day park hoppers with 4 plus options. The rest days were nice, but by 4 or 5 I was done resting, I wanted to be in a major park.
Do all the planning and research you want, you and your family will have a blast!!!
Maybe my son and I will get to meet you all during our trip. He's 11