Only blue theme color wedding will be too boring?

Is it okay to have only one color for my wedding? I'm getting married on a yacht, so I'm thinking to use blue as my color. My bridesmaid dresses is baby blue, the groomsmen will be cream vests with blue ties, my cake is light blue with white chocolate seashells, the bouquets will be white calla lilies + ivory roses + sky blue ribbon, and the certerpieces will also be ivroy roses + blue hydrangeas with seashells. Is that too "blue" and too boring?