You can do that with Xbox and Playstation 3 versions of the game. They have been posting downloadable Toy Boxes since the game's release which are available free. One is a rough model of
Disneyland. There are dozens available now...all free.
Unfortunately it's my understanding that the Wii's online shop wasn't capable of similar download functionality. Too bad.
Overall Infinity is something of a mixed bag to me. The Power Disc implementation is severely lacking. Of all the discs that are out now, my kids are only interested in maybe 8-10. Others just sit in the folder and will rarely get any use.
Characters which can only be used in the Toy Box mode are pretty much worthless. I understand why designers wanted to limit each playset to just its native characters, but there's not a whole lot to do with figures who don't have a playset. My kids got Ralph and Vanelope for Christmas. After 10 minutes of running around in Toy Box mode, the novelty had worn off.
If they make a Disney Infinity 2, I hope there is at least one playset where EVERY character can be used. The setting doesn't really matter.
I also hope they make all of the current figures backward-compatible with an Infinity 2 game. Skylanders does this.
Honestly I'll be very, very surprised if there isn't a follow-up game. There were reports that Disney spent $100 million developing Infinity. And most of the work is already behind them. In order to make Infinity 2, they can re-use the same base game engine. Just need to apply a few tweaks and build new Playsets.
Most of my local stores (TRU,
Walmart, Target) saw their Infinity stock dwindling throughout the holiday season.
But again, I hope they reward folks who spent literally hundreds of dollars on Infinity 1 by allowing most--if not all--of the discs and figures to be used in an Infinity 2.