In addition to the superb answer above:
"Men were deceivers ever." The main villain in the play is a male, Don John the Bastard. He dupes males: Don Pedro and Claudio. The play's hero is not Hero, but Beatrice, for she has the power to change Benedick, converting him to her gender's side.
Double marriages are better than a funeral. The play is a comedy; as such, it must end happily with union. At one point, the play seems headed toward tragedy, but Hero's reputation is restored and Don John is captured, resulting in two marriages instead of one.
Low comedy saves the day. There are two kinds of comedy in this comedy: high and low. The high comedy (battle of the sexes) is between Benedick and Beatrice in their clever wordplay. The low comedy (Dogberry and the watch), however, uncover the plot of Borachio and Don John. They unwittingly save the day--and have fun in the process.
The comedy is full of archetypes. We have two sets of lovers who are foils of each other (Benedick and Beatrice versus Claudio and Hero). The former are disdainful of love, and the latter are infatuated with each other blindly. We have two brothers who are foils (the legitimate Don Pedro and the illegitimate Don John). We have the villains vs. the watch. Alazons (those who think they are better than they are): the men. And Erions (those who are self-deprecators): the women. All in all, the characters represent the eternal love that we all share.
Here are also some other topics by Enotes and corresponding thesis statements:
Shakespeare interweaves two love stories in Much Ado About
Thesis Statement: The Claudio-Hero and the Benedick-Beatrice love stories are interwoven in Much Ado About Nothing through a series of parallels and contrasts in characterization, in dialogue, and in plot structure.
Appearance versus reality is the major theme in Much Ado
In Much Ado About Nothing, Benedick and Beatrice explore an unconventional path of love. Write an analytical essay on the lovers' journey in awareness, and the way in which Shakespeare uses syntactic structures to reflect this movement.
Thesis Statement: Benedick and Beatrice explore an unconventional path of love; a journey in awareness which is reflected in their syntactic expression.