My stories happen in a sci-fi universe. They usually happen on diferen planets and moons, and only at some occaisions collide. I was thinking what if all them happened in the same place. I have this 3 ideas for parallel dimensions where they all start on the same place: 1. A superhero city (like Marvel's New York). 2. A pro-wrestling company where it is the primary sport. 3. A constant war of lineages, derived a bit for a song of fire and ice. Should I have all three? I am most confident about the first one because there is no constant struggle for status like the other two. How can I pull them off? Any suggestions to improve either one of them?