Having grown on reading fairy tales from all parts of the world when I was young I was taken by surprise by the plot as it did not follow typical fairy tale. It is a reminder how easy it is to label someone evil just because we do not share common understanding.
The movie is treasure of emotions and being human. There is more humanity in Maleficent character than what are in 'human' characters. Humans in the movie are savage, greedy and treacherous, much like a lot of people in the real world. Movie reminds us that we are all prone to make bad decisions in our lives, and that when we are hurt we easily become evil, punishing ones that do not deserve it, while ones that deserve to be punished fare well for a long time.
Disney made a miracle with this one. Movie effects are magnificent and just enough to make it for the movie function, not more than needed. It is a pleasure for the eye as it is pleasure for the heart.
It transcends fairy tale and if you are ethical it teaches you a lesson. Not many movies and stories achieve this.