I know the challenge is image grain, but the horrible colors created are definitely at odds in this picture. Sometimes doing a partial desat to tone down the worse of the color (maybe the green/yellow and the purple) will create a more pleasing image.
I like the shot, though the grain comes off to me a bit more as chrominance noise than image enhancing grain. Not that it matters to me where the grain comes from, simply that it enhances the image. I popped this into my photo editor and it looked good with the same treatment I used with my own entry.