Originally, Lorimyr was a flat place with the stars and planets rotating above it on the crystalline spheres of heaven, similar to some of the medieval ideas of the universe. Since it started as a C&S world, and everyone and every magic item has a astrological sign, then it needed planets and stars. Also, since Lorimyr was created by magic, this fits right in with the C&S magic system, where everything has an intrinsic magicality.
I have decided that Belkar has over the years shaped Lorimyr into a round planet because of its size and seeing other places as examples. But it's a small planet, about 2000 miles across. And the sun is the same size and as far away as the moon (240K miles). The moon is 500 miles in diameter and 60K miles away. The other planets are similarly close and small, since there are no considerations for gravity -- the advantages of making your own universe magically.
Then I was thinking about the Renaissance meme of exploration. This is manifested in Lorimyr in an effort to explore the physical universe, to delve into the secrets of magic and science, to study other planes. Being a Renaissance TL 4 world, they have sailing ships. Someone is going to get the idea of exploring the planet, perhaps with magically-levitated ships. And someone is going to see if they can sail to the moon.
So, I can see my way clear to a Renaissance Planetary Romance/Sword & Planet setting. This is very exciting. I may have to write some fiction for this.