I like your first one to be honest.
Well, it's not difficult but you need patience with this kind of job. First of all, you need to find 4096x2048 or bigger textures (google maps or just google images) for the planets. Finding this for mars, or jupiter is no problem. But for the other 150+planets, well that's a different story. When you have it, it's not just copy and paste, because the texture fits around the sphere(planet) and if the two textures aren't the same, well the "zipper" won't close properly, and you have big visible line (of the texture hitting each other). So you need to make sure that they fit properly. If you've done that step, great! Start doing it with 149+planets
But you need to make sure, that there is a nice variety of planets. (you got to find another huge batch of big filesized textures). So, you are quite busy with finding them, changing them(different colors) or cloning ugly parts away or adding parts. So i've done that part. But a few planets are heavily in the loading part, so you need to change those to.
As you can see, it looks easy, but it takes a lot of time. Also the nano fx atmosphere gfx is a huge bummer on the planets, so i redone those textures as wel.
