The decision for the time line will simply be whether "7:30" or "half after seven o'clock" best reflects the tone of your wedding. Formal events call for spelling out numbers, whereas that might seem out of place for a more casual wedding. The same holds true for numbers in the date line and those in the location line, if, that is, you include the street address. Remember that all options are equally correct.

Also think about whether you want to say "Reception immediately following" on the face of the invitation or whether you'd rather include separate cards to announce your reception. A separate card is only necessary if you don't plan to invite everyone to the reception.