Lots of things to think about here. I had to concentrate on the stuff that's most relevant to the story.

I know that as I progress in this, I'll have to come up with more. Everything is interconnected, even across interstellar space, and something that may seem trivial now can influence events disproportionately once the ramifications become apparent.

There's a trap a lot of science fiction (and fantasy) writers fall into, which is to give each planet one defining attribute. Arrakis is a desert world. So is Tattooine. Hoth is an ice planet. And so on. They become nothing more than expansions of a single ecosystem on Earth, at which point you start wondering why bother having other planets at all?

Any planet that's going to support life is going to have diverse ecosystems. Probably. Even if a planet's entirely covered in water, the ocean near the equator is going to be different than it is near the poles, because of temperature differences. Exceptions might exist; we don't know. But even Mars has different zones, and a volcano that pierces the atmosphere, and ice caps, and it (probably) doesn't support life.

Imagine a flying-saucer alien crash-landing in the Sahara. It might think Earth is a desert planet. One that crashes in the Amazon will have an entirely different perspective.

So I try to keep that in mind when designing worlds. Most of them will have more than one ecosystem, terrain, or climate.

Dang it. I'm going to totally steal this from myself for the next Fantasy newsletter.