I've been thinking about terraforming and planets in general.
We can look at the planets we know that might be terraformable - Venus and Mars - and understand the technical requirements for doing so. We can even imagine other planets and what might be necessary for them.
What I'm trying to create is a planet that has no indigenous life, but yet is remarkably easy to settle; it needs little or no terraforming work at all -- the temperature is just right; it has oceans, land, rivers, soils that can support plants, maybe even a nice big moon to produce tides. Basically, it's Earth's sterile twin.
But I'm aware that a lot of the things which make Earth great for life are actually a result of it having life.
So the question is: How feasible is my scenario? How perfect can I make this planet without it ever having had any life to help make it perfect? What compromises will I need to make in order to make it realistic?