Another way to look at this concept is the plot within a plot design. We have several plots in this play. One is Titania and Oberon's fight over a young servant boy. Another is the young lovers' troubles (Lysander, Demetrius, Hermia, and Helena). You also have the love story of Hippolyta and Theseus. Another is the artisans story, with Bottom, Snug, Peter Quince, and the rest. Finally, you also have the play within a play with the love story of Thisbe and Pyramus, which mirrors Romeo and Juliet in many ways! All of these plots make the story very unique, complicated, yet endearing and funny.
You can look at it as all of the subplots circling around the main plot of the young lovers. The main action centers around them; yet, the subplots are also connected to them in one way or another.
Another aspect of patterns and design is the focus on the fairy world, on the one hand, and the mortal world on the other. The play not only mingles the subplots, it mixes the mortal worlds and fairy worlds.
The structure of "A Midsummer Night's Dream" has been analysed in great detail by many Shakespearean scholars over the years. The structure of the play continues to be studied in the light of contemporary critical theories. Of the innumerable ananlyses, a simple and easily understandable one is by Mark Rose (1972) in his book "Shakespearean Design".
Mark Rose considers the play as two concentric circles with Act III sc.1 as the central scene.
The outer circle comprises Act I and Act V with the action taking place in Athens. The inner circle comprises Act II and Act IV with the action taking place in the Athenian forest. Act III sc1. forms the centre in which the love of Titania for Bottom brings together the world of Athens and the forest.