A "theme" does not have to be "fishing" or "Chicago." It can be a monogram that starts on your invitations and then is replicated on your wedding cake and personalized gobo. It can be a color or flower that your guests see repeated on all of your wedding stationary from the save the dates to the thank you cards as well as the cake and centerpieces.
I thought that this was an ADORABLE wedding theme for two people who met in elementary school. It could also be used for two teachers getting married. It's elegant, classy yet personal and so very much the couple.