my kids look about the size of your kids. They really enjoyed SSR this summer. The Community HAll was a fun place--go even when there are no scheduled activities--we did not do this until the end of our trip, and it was their favorite palace--PS2 games, coloring, painting, games, and a disney movie playing on a big TV with a sofa to watch.They also had fun pool games for this age. My kids loved SSR pool--it has a great slide.
We only went into parks 2 days. We did pool AM, Community HAll after lunch, then either character dinner at a hotel (so we didn't have to pay park entrance) or Ft Wilderness campfire and CHip and Dale sign along, or went over to DTD for dinner and played at
lego store. They also have movies at the Grandstand pool 3X a week (we stayed in Grandstand---it has it's own pool and sprayground and hot tug---but still close to Springs for food and big pool--great section to request).
AK is a great place---but I might save it for another year when all the construction is done and everything is up and running. Kids say AK slide is "lame" and pool is boring--I love it, but I'm not a kid.