Forget the crowd calendars. If it's not super busy, you've caught lightning in a bottle. I would be concerned however, with doing parks on EMH days as you suggest. Personally, I would avoid MK on Mondays but I can appreciate you wanting to sandwich your trip with that park.
Not really much there for the young kids, outside of Frozen. For me, the highlight of WS is definitely the American Adventure show. The films in the other pavilions are really dated, as is the boat ride in Mexico. I'd hit Frozen for the kids, and maybe consider the others if I had left over time.