A few years ago I created my opus. It was a detailed Science Fiction Universe. It had 88 systems with multiple planets in them, nearly 300 planets. I used the Dragonstar setting from Fantasy Flight Games. This was a D20 setting wherein dragons, through their superior strengths and intelligence gained control of a star-spanning empire. The usual fantasy tropes were included; magic, elves, etc but it was a science fiction setting with lasers, spaceships and power armor suits. In all is was a very interesting setting.