To start, the 3D to me was just incidental. When they made the effort, it was amazing. But it doesn't make or break the movie.
The storyline is delightful, and I'm embarrassed as an adult to say this, but the character development was excellent. The green message or nation-building (or both) message is obvious.
This is not really a child movie - the language and war scenes, etc. The battle scenes are too long.
But my husband and I enjoyed this immensely and would recommend it.