Think about your wedding in different acts. Each part of your wedding is a different stage and each one can have a different theme. You don't need just one theme throughout your whole day.
Traditionally a wedding has three acts - ceremony, drinks/cocktail hour and dinner/dancing - but you can add more such as a separate dessert area, an after party/night club.
And think about how your guests are going to get from one area/part of your wedding and make each act an experience.
By having different stages/themes it keeps your guests excited, interested and guessing what is coming next.