I really like Spire Island, but am amazed how much you were able to put out.
Well, I had all these old projects and this contest made me realize that if I create a scene, I make more than is needed for one POV. I like to make it a big as possible and go exploring. And TG itself makes it easy because surface shaders are global. So all I need to do is just add or extend a population here and there, paint a line of a path, or in some places place another height field behind the original camera.
The cave scene had even more cave than I realized. So when I found an exit, I was surprised, but then I had to cheat to fake an atmosphere. The scales of the planets was so big that I had deactivated the atmospheres, because double atmospheres make crazy render times. So I made the background object sky blue, an placed a light like a sunlight near the entrance... Had to tweak that quite a bit.
So for most scenes I submitted, I only had to place camera's along an exploring path, as I would do when first exploring a new place where I go in real life. And then tweak stuff a little if it didn't look good enough.