Regardless of when you go and whether it is an EMH morning or not, you can get a lot done at all the parks if you get there before opening. Last June we got to see Mickey's Philharmagic with about six other people the first thing in the morning. No waits at all on Big Thunder or Splash Mountain. We even walked onto Buzz Lightyear a couple of times before the lines formed. Tomorrowland denitely gets more crowded than the other side of the MK early in the morning. Rode Tower of Terror with no wait and then jumped back on line again. Test Track and Soarin' get crowded really early so grab FP, get on stand-by or use single rider line if it's open and it's an option for you, then ride again with your FP almost immediately after your first ride. The big crowds normally don't arrive until later in the morning. By noon or so we leave that park for a resort break and then head to another park later in the day.