Wow the lighting looks superb on that second one! Well done on that Placement is fine and so is the amount of content. But try to make your work ALOT bigger. Eg: 2000x2000pixels ... then resize to 800x800 or w/e. When you work larger you have to incorporate more detail, or even if you don't, when it's resized detail will appear! The textures on the planets just look embosses, and the outer glows look very fake and the colours don't work. And you would also not be able to see stars near the sun, but the sun looks quite nice Keep working at it, with more skill your ideas could be good :P