lets do this!
but my way would be to make the second weekend essentially a "worthy pastures" weekend... Worthy Pastures was wonderful and for me captured all that is special about Glastonbury.
they still dismantle the festival right after, but leave up the fence another week, keep a bunch of food traders and a couple of bars in place.
first weekend for people who want to be in constant over crowding, watching a bunch of crappy Wireless Festival rejects.
second weekend for people who want to enjoy being in the beautiful place that is Worthy Farm.
🙂