The Taming of the Shrew, A Midsummer Night's Dream, The Merchant of Venice, Much Ado About Nothing, and As You Like It all end in the celebration of the marriages of multiple couples. In Twelfth Night the marriages of two couples is assured, but the final part of the last scene focuses on Malvolio's anger.
All of the six plays portray love mistakes. Suitors are too old, or too silly, or too egotistical. Or someone may be in love with a boy who is really a girl, or with a man who is really an ass. Or a couple may quarrel epically, then fall in love.
Character Types
All six plays have at least one heroine who challenges the emotional clichés and societal pieties of the time. She is often contrasted with another, much more conventional, female character.
All six plays have at least one clown. -- Clowns seem to fall into two types: The buffonish, the most famous of which is Dogberry in Much Ado About Nothing, and the witty fool, exemplified by Touchstone in As You Like It.