Could do worse.
But this could use some work.>I am still trying to find a way to add more focus to the dude without taking away from the feeling of vastness.
You can do this by giving the image a wider angle, pulling the camera back, and making the landscape more substantial. Think about how horizons work, and how distance and scale interact.
As for separating the guy from the rest of the scene for focus, read up on composition techniques and how the eye moves over images. Putting him in a good spot with that will help you a lot, as well as contrasting colors to make him pop out more.
If the blue thing is supposed to be another planet, MAYBE try adding some atmospheric perspective to give it that far away look, and to emphasize the scale.
You're a bit late to the party as far as the low poly trend goes, but it's quick to pick up, and is easy to concentrate on constructing how a scene looks instead of minute details.
Pic related was one of my early projects when I got into this sort of thing.