Kastimund in tow.
"Good morning, creator," he says, a hint of dry.
Then says, in the tone of voice meant for interpreting Saerith, "'The most important thing of all is getting all of the spirits in, and trying to capture how we interact with the foundation and formation of the world itself. If you can get that right, you can get a world that's functional, if kind of boring. As a priority after that, I'd recommend trying to get Esere's magic system copied, because it's easily the tidiest yet. From there, geography and ensuring biodiversity are important - varying rock types so you can compare what makes them different in the terms of the magic that creates them, and plants and animals and the like. Ensure that the land is varied, in case people turn out to need or want things you hadn't been expecting when you wrote the world.
"Once you have a decent foundation assured, you can just cheerfully drop whatever you think the world might need. Books especially - you can preserve a lot of the accumulated scientific knowledge that way, but buildings, roads, bridges, plows and the like would definitely be appreciated, rather than dropping people in a new world with no supplies. But I would like to stress that while they're definitely useful, they're - the proverbial icing on the cake, your priority is making the world itself stable and long-lived."