If you want to go the modeling and level design route then go to the websites of 3dtotal and cgtalk and look what game artists do there. Now you only have to reach this quality. But be warned: It will take you a few years. But first lay down your 3d modeler and pick up a pencil. You will learn much more about lighting, shading and anatomy if you create your own drawings first. Then you can apply all this to the 3d world.

Your competition are women and men who started to draw in their childhood. They do it with passion, they did sketches in every book at every sheet of paper available at almost every time.
So competition is tough in this area. My suggestion is to practice every day to catch up with them.