With young girls, I would think that FEA is your FP priority. (Though Soarin' would absolutely be mine!!)
Hit Soarin at rope drop.
If your kids were older, I would say use the single rider line at TT, but I can understand that it might not work with kids that young.
Would you consider 2 mornings at Epcot? Then maybe a hop at lunchtime to, say, Animal Kingdom? You can do most of AK without a FP.