The Disney Infinity game is actually a series of different games based on different movie properties. Each game can only be accessed with characters associated with that movie license, so your replayability is limited. That's because the big thing in Disney Infinity is supposed to be the toy box, which is essentially a level creator. In user-created levels, any character is accessible, which is good because...
Some of the Disney figures can't be used in any of the games. That's right. From the 2nd wave of 12 figures, only 3 can actually be used in actual pre-made game levels. The other 9 are only usable in the toybox mode. But hey, who wouldn't want to buy a figure of Jack Skellington even though if you want to play as him in the game you have to build a game level yourself... WHAT THE HELL IS GOING ON?!
But I pre-ordered him because I was curious, and after having him run around my horrible pre-made level... I don't know if I'm going to buy any more of these non-game figures. Because really, without goals and objectives, it's all pretty damned dull. Which is insane, because the way they designed Jack's moveset, they could have just dropped him in the Monsters University game with no problems.
At this point, if Disney Infinity wants to become "fun," or at least justify its price, it needs to let you play as different characters from different properties in all the levels.
And leveling up doesn't get you anything. No increase to stats, no unlocked abilities. It's just leveling up to make a number go up. That completely ignores the addictive property of level grinding.
All these problems I'm mentioning here, they've all been addressed by Skylanders Giants, which is costing me more money, but which I'm having a LOT more fun with. When you level a character up, your stats increase. When you acquire money, it doesn't just unlock the next part of a game level, you use it to buy new abilities for your character. Oh, and EVERY CHARACTER CAN BE PLAYED IN EVERY PART OF THE GAME! Replayability is all there. And the game play is combat based and fun, it's not just a bunch of fetch quests or collectathons which is pretty much what most of the Disney Infinity Game feels like. (Although Skylanders has both, they're not required to advance gameplay, just to unlock bonus items.)