It's good, but lacking something...
I always find that a lot of the fun in adventure games is not only solving puzzles, but also interacting with all kinds of things. For example, there are dozens of potential creatures, people and items to interact with in this game, but most of them are unused - only that which gets you further in your mission is really interactable with. That's a pity, because the game's style and programming are really great and the world really "lives". Adding all this interaction would make the game a lot more fun, even if it's all irrelevant to the plot, plus it provides for an opportunity to create, define or at least show character's personalities a bit better.
tl;dr: great graphics, nice music, beautiful surroundings - but not enough interaction.