I don know how powerful gimp is compared to photoshop.| but U need some render effects... and/or retouch the render with better coloring.| The text is mad plain too. Much work needed, judging gimp is similar to photoshop.I like the simple BG tho cause u can probably create something very creative but simple looking with it.
Pretty good for GIMP, but I think you should do with an all white BG to match the render...also add some render effects and your money.
