Here's some things that I would do:
Magic Kingdom:
-Make Town Square go back to bringing out mostly random characters out for meet-and-greets, where the characters that appeared varied from day to day. Possibilities could include:
-Clarabelle & Horace
-Clara Cluck
-Clarice
-Max Goof
-Peg-Leg Pete
-Ludwig von Drake
-Scrooge McDuck
-Huey, Dewey & Louie
-The 3 Little Pigs
-Big Bad Wolf
-Bernard & Bianca
-Gurgi
-Basil
-Ratigan
-Roger Rabbit
-Oliver
-Dodger
-Launchpad MacQuack
-Darkwing Duck
-Rebecca Cunningham
-Kit Cloudkicker
-Don Karnage
-Gadget
-Monterey Jack
-Fat Cat
-Bonkers
-Have Donald, Daisy, Goofy, Pluto, Chip and Dale appear in the Expo Hall, in the same new location that Mickey and Minnie are going to be moving in to.
-Bring Rafiki and Timon back to Adventureland and have them rotate with Baloo and King Louie.
-Have Genie and Abu appear regularly at the Aladdin Magic Carpets. They could rotate with Aladdin & Jasmine.
-Have Louis the alligator come out for regular sets, rotating with Tiana & Naveen at their gazebo in Liberty Square.
-Bring Captain Hook & Mr. Smee out for regular sets again and have them rotate with Peter Pan & Wendy in Fantasyland.
-Bring the 4 Country Bears out for regular meet-and-greets in Frontierland again.
-Have Brer Rabbit, Brer Fox and Brer Bear go back to doing regular meet-and-greets near the Splash Mountain exit.
-Give Jack Sparrow a permanent meet-and-greet location near his attraction in Adventureland.
-Characters that I'm hoping they'll add to Fantasyland when its big rehab is complete:
-Gaston at his tavern.
-Dumbo near his newly-relocated ride.
-Other Cinderella characters (Prince Charming, Jaq & Gus-Gus, etc.) near Cindy's attraction.
-Prince Phillip, Flora, Fauna, Merryweather and Maleficent near the Sleeping Beauty attraction.
-All the Robin Hood characters near The Friar's Nook.
-All the Pinocchio characters near their Village Haus.
-The 7 Dwarfs, the Evil Queen and Snow White & her Prince near their ride.
-Other Little Mermaid characters (Prince Eric, Chef Louie, etc.). near the Little Mermaid ride.
Epcot:
-Remove Daisy and Stitch from the main entrance area and replace them with Kim Possible & Ron Stoppable.
-Bring out all 3 Caballeros at Mexico.
-Have Mushu rejoin Mulan at China and add Shang as well.
-Bring out all 7 Dwarfs at Germany.
-Bring Genie back to Morocco
-Bring the Hunchback characters (Quasimodo, Esmeralda, Clopin, etc.) back to France.
-Bring Mr. Toad out for sets at the United Kingdom.
-Bring the Figment meet-and-greets at the Imagination pavilion back.
Disney's Hollywood Studios:
-Add Clarabelle, Horace, Clarice and Roger Rabbit to the meet-and-greet sets at the Sorcerer's Hat.
-Bring more of the Toy Story characters (Jessie, Bullseye, Bo Peep, Mr. Potato Head, etc.) out for meet-and-greets at
Pixar Place.
-Create a new Muppet meet-and-greet of some kind.
-Eliminate the V.I.P.'s (Minnie, Goofy, Pluto, Chip, Dale, etc.) from the "Fantasmic" meet-and-greet sets in the Animation building and add the following characters to the list of possibilities for those sets:
-Cruella de Vil
-Bert
-Baloo
-King Louie
-Robin Hood
-Maid Marian
-Little John
-John Smith
-Hercules
-Meg
-Phil
-Hades
-Pain & Panic
-Shang
-Mushu
-Shan-Yu
-Dopey
-Maleficent
-Mr. Walrus
-Quasimodo
-Esmeralda
-Phoebus
-Clopin
-Frollo
-Tiana
-Naveen
-Louis
-Dr. Facilier
-Remy
-Emile
-Bolt
-Mittens
-Rhino
-Lewis
-Wilbur Robinson
-Bowler Hat Guy
-Carl Fredrickson
-Russell
-Dug
Animal Kingdom:
-Bring Kenai & Koda back to Camp Minnie-Mickey and have them rotate with Thumper & Miss Bunny.
-Have John Smith join Pocahontas at either of her locations.
-Bring Princess Atta, Mowgli, Tarzan and Jane out for regular meet-and-greets alongside their respective co-stars.