There are countless Disney items being released each week. I would think there are more items available in myvmk than were created for the original game....and there is an almost endless supply that could be produced based on the quantity of Disney and Pixar movies. The staff has really done a tremendous job balancing keeping a steady supply of new items and recolors to meet our ridiculously unrealistic expectations for the game. They created an entire month around The Incredibles which was based on all new items! While I'm not remotely qualified to be a designer, there are so many items that the creatives could design to keep the game appealing for years to come. Here's a few off the top of my head.
Toy Story RC Car pet
Toy Story character dolls (in and out of their original boxes)... that one could be fun with different rarities for the boxes (kind of like the blind bags)
Frozen rooms and furniture
More pins based on real Disney pins (like the Dress Up Stitch)
Continuations of existing pin series created in the style of the originals (perhaps a Jungle Cruise II or Haunted Mansion II set)
Winnie the Pooh furniture and ride start
Carousel ride start
Rock-n-Roller Coaster furniture and ride start