Lesson from Pennsylvania?
Maybe states shouldn't be so all fired-up to have their primary first (or nearly so), but instead try to schedule the primary as many weeks possible after the last one held somewhere else
in the nation. Pennsylvania had six full weeks of campaining (and spending). Contrast that with California, which was part of a big cluster of states. California didn't get anything like the attention Pennsylvania got. So maybe states will try and space their primaries out a bit more, lessening the silly rush to be first (when the result is more due to name-recognition than issues or campaign competence).
I think after this fiasco, the party leaders are going to be very careful to try to ensure that things are over as quickly as possible. I wouldn't be surprised to see far more "winner takes all" contests like the republicans have.