Well, I do realize that the current management at DL was hampered by what was left behind by Pressler and Harriss. This didn't leave them with much room to do as much as they could have.
Hypothetically though, if I had an unlimited budget to plan the 50th, I would have done some things differently.
First, I would have gone with the updated of 5 classic attractions that was proposed early on. Pirates, Haunted Mansion, Splash Mountain, Space Mountain, and the Jungle Cruise. Some of those attractions did get spruced up additions, but I would have gone further.
The fireworks show is probably something that I would leave alone, because it seems great.
The parade looks nice, but I think I would have done it differently. I would have had two new parades. One during the day, and a new nightime parade. The daytime parade would be a history of Disneyland, and each float would represent a land at the park instead of characters from Disney films. The nighttime parade would be a light parade, but something new, and NOT a "streetacular". More like MSEP or Fantillusion. Not DreamLights either. I would try to get Bruce Healy to do the score.
Next, although "Snow White and Enchanting New Musical" is new, I would have ditched it to create a show that celebrates Disneyland. Something like "Disneyland is Your land", but updated.
I would also have a big promotion like the 30th and 35th with their giveaways and drawings. Every 50th guest would get a surprise gift. Every single guest going through the gates would get a ticket for a prize too.
The 50th Exhibit at the Opera House would also have been bigger, and I would have put it into the Innoventions building where it was originally proposed.
I wouldn't bring any classic attractions back, but I would go in the direction they are heading with Tomorrowland, and revitalize it.
I like the gold vehicles thing, and the other touches in the park, that would stay.
I would bring out TONS of obscure characters to interact with guests. Ones that have not been seen in a long time, or ones that have never been seen.
The one thing I might also do, although I don't like the idea of bringing old attractions back, I would get old attraction vehicles and put them up around the park for photo ops. Old peoplemover cars, skyway buckets, Autopia cars, and what have you.
I would have rushed to have Buzz Lightyear open, as well as negotiated with George Lucas to create a new Star Tours film before the 50th started. I would have thrown a lot more money at Space Mountain to make it a totally different experience (that would have been part of the classic 5 update).
I would recreate menus from the opening of Disneyland and serve food that was availible at the time...and at cheap prices. Some of the souvenirs too.
I would have really pushed the marketing budget too, so that everyone around the world knew it was Disneyland's birthday, no matter how much WDW advertised. Maybe create another short film to play in theaters much like the "Disneyland U.S.A." short. And NOT overly commercial either! Basically shine the spotlight directly on Disneyland so that everyone knew where it all started.
I'm sure I could think of more, but I've done enough armchair planning...