It's a pleasant literary task. Children and adults alike are captivated by tales of the sword and the stone in King Arthur's court. Yet, little has been written about the early years of Merlin's life, the time when he was a boy just discovering his powers. T.A. Barron calls these the lost years of Merlin, and has written a series of books devoted to the young wizard. T.A. Barron weaves an environmental message through a tale of spells and adventures.
Stories somehow get into our consciousness in a very powerful way.
I don't think there is any more effective means of getting a point across. You think of all the great storytellers who have made important points in their day, whether it's Rachel Carson or John Muir or Chief Seattle, for that matter. They knew the power of a good story. Now, you choose to write stories. I'm wondering why you choose to focus on an ancient mythological, magical figure, Merlin.