This sort of happened to me with the design from the Renew Derby back in December. I did this hurriedly, and was okay with it enough to submit, but I knew it wasn't what it could be. The white outline bothered me the most. It cartooned a design intended to be more serious.
It didn't win, and after the sixty day waiting period, I came back to it and was ready to "finish" it. I modified it so it was no longer dependent on the outline, redid the shading on the waves and added more realistic shading to the horn. I'm a lot happier with it now. It's currently being scored here at Threadless. I'd love to get your comments there if you have some time.
So when you're shopping around for possible new homes for designs, always ask yourself if it's finished. Sometimes they are, but a lot of times you'll find opportunities to take them even further.