I personally would do individual serving size pies rather than having the catering staff slice full sized pies. Also, you could stack small individual pieces on a tiered cupcake rack and get a wedding cake effect...sort of a compromise between tradition and innovation. One could even put a cake topper on top of the stack of mini pies, were the bride and groom so inclined. There are plenty of couples going to cupcake route for weddings. I think it's a very fun idea.