Lowering the cost for food at a reception
Instead of having a full meal, just serve dessert. The guests are there to celebrate your marriage, so you shouldn't have to worry about feeding them.
Have your reception at a later time, so that people have already had dinner. Ask family members, friends, people from church work or other groups to bring a predetermined dessert.
Some elegant looking desserts could be lemon bars, pistachio pudding dessert, even brownies are simple and everyone loves them.
Fresh fruit can be cheap and provide a variety of colors for a beautiful look.