I promise, promise that these plans work even if you're spacing out your fastpasses! Like in MK, if you are there at ropedrop to do Fantasyland, you won't need ANY fastpasses to see all of those attractions in the first hour or so. We tend to split up MK, too, and usually do FL, Liberty Square and Frontierland on one day and leave Tomorrowland and part of Adventureland for another and the touring plan doesn't do it exactly that way. If you follow a plan at least until lunch I think you'll get in everything you want to do in a day.
Also, one thing I have learned with a dd who has been 5,6, and 7 on our last trips is to allow some time for autographs and pics with the characters. The ones in the parks didn't eat up too much time at once, but Toontown seemed to eat up some time. I would save it till your second MK day and stick in into the plan in the morning where you will have already done Fantasyland and Frontierland.
DHS is just hard, even with a plan because of trying to fit in the shows. Will you and dh be riding Tower of Terror and RNRC with child swap? That is what we did and still managed to stick mostly to a plan. For me, it is a very angst filled park to schedule!