Over the years we have done a number of 7 AM EMH at Easter and Christmas. You can do a lot between 7 AM and 10 AM.
Our approach has been to go to Space Mountain, then Buzz, then maybe one or two quick rides in Fantasyland (choosing from Dumbo, Barnstormer, Little Mermaid, Pooh, Teacups) and then hitting Peter Pan at around 7:40-7:45 with the idea of getting off of it before the rest of the park opens at 8. Of course, the mine train will change the early pattern. We might start there, then hit SM and Buzz and then go to PP if it's getting closer to 8. If we can do 2 EMH days in one trip, we will do a lot of the other things in Fantasyland and Tomorrowland the second day.
We like to be in position to go toward BTMRR and Splash when the rest of the park opens at 8.By doing that, we can usually do those 2, then POC, JC, and HM in less than 2 hours. So, by 10 AM we will have done what we consider our top 8 rides and still have time to do a couple of other things with short waits before lunch (which we usually have early when we get to the park before 7). Then we can slow down and do some of the "anytime attractions" after lunch. We usually don't make our FP reservations until after 5 PM, and those are usually at a different park. If we get tired, or if the park gets too crowded for our tastes, we may take a break back at the resort before hitting the second park.
Those are great days!!
If you want to focus on Fantasyland, I would think you could do most of the attractions there before 8:30, though I wouldn't do IASW too early because it takes so long and will still have a reasonable wait up until 10 or 11, if not longer. If you want to do both, you would have to do the mine train and PP quickly because the lines there will build up fastest.
