The main feature should be the teaching of principles through stories. Don't make it metaphysical at all.
Swami Vivekananda. . . it is difficult for Europeans to appreciate the sentiment. Other nations kill animals by wholesale and kill one another; they exist in a sea of blood. A European said that the reason why in India animals were not killed was because it was supposed that they contained the spirits of ancestors. This reason was worthy of a savage nation who are not many steps from the brute.
Swami Vivekananda