Oh I love that fishie blanket.
I just found out I am to be an aunt too! This will be a perfect gift for the young'un (i just love that word lol) and let me use up my stash of simply soft. I think I can make 2 blankets with what I have!
I second the "any color" opinion for sewing it up. You could even try an ombre yarn so that the color changes randomly for you.
You could also try a unifying color - all white, grey, black, navy, etc
But I like wild best.