In one sense, it's best for an author to write about what he knows. Since I've only lived on Earth, shouldn't I write about that? However, I've also spent time analyzing the imaginations of different authors and animators. When you have all of that, it's hard to write only about Earth and so crafting a new world is the best.
So what does this mean for my story? Well for one, I'm allowed to craft my own creation myth. I can also play around with the nature of characters and their biology. For instance, I have yet to decide whether or not my characters can be called "humans," just like Tolkien and his predicament with the "elves". However, since it would be too much of a pain to come up with a new term and get my readers to grasp it, I'll just call them humans as the nature will be very similar. There are a couple things I'm want to play with but morality and that side of nature will still be the same. I hope you are looking forward to what I have planned.
J. D. Nyle