i agree with sleeping in!
we always feel that when the park is open, we need to be IN THE PARK. we rarely leave for "breaks" whether we are staying on site or off site.
when we went in May we were dragging so bad by the end of the week and barely even getting up in time to get ready for early entry and such.
for our Sept. trip, i'm actually looking forward to a later opening so i can get up and eat breakfast and dress kids and not feel so rushed and tired.
however, if you are an early riser, i recommend a character breakfast for sure with PS prior to park opening.