Your wedding day is the one day where everything should be perfect including the cake. The best way to have an absolutely unique and interesting cake is to design one yourself with help of your wedding cake provider.
Set a budget and sketch a few cakes that would fit your wedding color scheme, theme, and financial spreadsheet. Discuss the alternatives with your provider and be ready to compromise especially if the budget is tight.
These wedding cakes may not be perfect for everyone but hopefully the bride and groom liked them.