Keep this sense of wonder and flexibility in mind when deciding what you'll allow as PC choices as well. I know there's been a some virtual rumblings about dragonborn and some of the newer D&D races from folks who (like myself) were weaned on Tolkien. But you have to realize that fantasy is a language, and that languages expand and change -- especially when the language is discovered and loved by younger users. When I was a kid, all I wanted to write, draw, and paint was the fantasy of Moorcock, Leiber, Howard, and Tolkien . . . and of course D&D. The adults around me told me I was wasting my time. Often, cruelly and with much certainty, they said the flights of fantasy I loved were dumb, or pedestrian, or childish. They were wrong.
Now the tables are turned, and I'm the adult. It wasn't so long ago that I sat in a meeting at my other gig -- as an instructor at a local art school -- and I sat around and listened to other instructors complain about how the kids liked drawing all this over-the-top anime fantasy. They called it childish, pedestrian, and a waste of time. Guess what: They're wrong, too. What those kids are drawing is the future of fantasy and it's coming fast. If I were you, I'd do my best to understand it and embrace it, and go out of your way to find a fit for it in your game world. Join the conversation instead of denying it! One of the greatest strengths of D&D and roleplaying games as a medium is the shared aspect of it. Sharing is compromise. Sharing is being flexible. Sharing is saying yes. Sharing is fun!
Wisdom and Genre Evolution
In an excellent essay on being a more open DM by Stephen Radney-MacFarland in Dungeon, this brief section struck me as being a good encapsulation of a larger truism about genres in any art/entertainment form. And life itself, perhaps: