I wanted to stay away from the ones that every other freaking guild was using. If you wanted trite, go with the black and white skull. People try to be funny all the time. Hell, I've seen a really cool Lobster Dinner Bib one. The Soup one has been used often also.
The Blue comes out with a bit more shine in the game, and the yellow boarders on goldish color.
Pink just looks bad in the game that is already brightly lit and overly colorful, and black/white tends to be used away to often.
But I would go with the skull one, I just didn't want to be the one to suggest it.