That which I most have notice about games based on books, comics, cartoons, anime, and movies (particularly Disney), is that typically the developers demonstrate very little faith in the appeal of the end product thus avoid spending too much of their resources on fleshing out what consumers would consider to be a full game experience.

Kingdom Hearts aside, generally all videogame adaptations of other properties are expected mostly to be novelties pandering to fans while offering very little in the way of length, substance, narrative, or immersion. When I play a game based on Incredibles or Monsters Inc or Frozen, I want to really feel like I'm in that world, not just tagging along on an otherwise unrecognized extraneous sidestory or rehash of the known narrative. If I'm gonna invest in an interactive romp through a recreation of the world of 300 or Triple X, I want to experience that world, not some half-hearted half-baked moneygrab.

It's a sad cycle like obesity and depression and comfort food: developers feel these games won't make much money; after all, the appeal of such a novelty barely applies to the target fanbase, but therein lies the problem. As earlier mentioned, Kingdom Hearts has been able to adapt multiple properties, but it isn't the Disney fans that bring in the money. Games need to appeal to fans of a specific GAME genre. Then after every aspect of the pursued genre should be put in attempt to make this the best game in that genre if not overall.

Personally, I tend to lean more heavily toward these higher loftier expectations for games, particularly if I'm being led to believe it is in the world of a place I'm already vaguely familiar with. I'd like an in-depth romp through a place like the Norse isles of How To Train Your Dragon or a globe-trotting adventure with Jack Frost and the Guardians. But chances are more likely to be stuck just under an hour of relevant gameplay in a slapped together narrative based loosely on the source material a la Rise of the Underminer.