Some really good ideas here!IF you want to make it less crowded you start by eliminating the things that make it more crowded or rather feel more crowded.
FastPass must go. The way it works makes the park seem more crowded by taking out people from E-ticket ride lines. It also makes the E-ticket ride lines longer for anyone that doesn't have a FastPass. If you are in a spot that might have been a 1 hour wait in times without FastPass, with the FastPass bumping you that line is now closer to 1.25 hours. And all you got in the exchange for that is taking the people that would have been in line for an E-ticket ride somewhere else, be it a C-ticket line or just walking in the park, all they did was increase the time people wait elsewhere, increase the crowds in the parks non-line areas and make the lines move slower in the E-ticket rides....
Next cut back on the things like Fantasmic, the parades and fireworks. These things create huge crowds of people for hours before the event even takes place. Does the park need 2 showings each night of Fantasmic? multiple parades? Or even nightly fireworks.... Save some money and eliminate the crowd magnets by rotating them... one night you get a Fantasmic, the next a parade, and then fireworks.... Now not only have you lowered the number of crowd magnates you have also created a reason for a customer to spend 3 days in the park instead of 1.
And last but not least.... Raise the prices... Supply and demand says if you raise the prices higher the crowds will be reduced... or eliminate all multi-day tickets and passes and go to a single day only ticket model... Or better yet go back to the book of tickets for rides as they once had... Then you can price the E-ticket rides more and balance crowd control to specific rides. When a new Pirate movie comes out you ratchet up the price of that ride to control the lines.