One of the most important things that needs to be understand in any form of art is composition. It doesn't matter how much detail you've put into a project if your composition is off. An image with bad composition will quickly be uninteresting and the viewer will simply move on. It is only when the composition is done well that the viewer will look into and appreciate the detail you've added.
Andrew Price AKA the blender guru has a very helpful video explaining composition and the multiple ways it can be achieved. It won't take long to read and you will gain so much insight from reading it. Here is the link: