A proper wording is a balance between your taste and certain factors over which you have no control. This includes attention to military personnel, judges, mayors, doctors, and so on. The spacing between the lines Your FONT is selected based on what you have in inventory combined with the tone of your invitation. A formal invitation dictates an elegant, formal font not often available on your system. So you go buy a 'font collection'.
Cheap fonts abound.
Aside from the beauty of the design, the technical implementation of the design is very important. A quality font is technically well described . . . A cheap font of the letter 'O' when enlarged will be made of discrete lines. Your FONT SIZE is equally important. Most Invitations are printed somewhere between 18 points and 22 points.