This is a great question. While Brutus is often considered the tragic hero of Shakespeare's Julius Caesar, many readers and audiences of the play have insightfully noted that Brutus, for all his honor, is not always the best leader. Indeed, it could be argued that Antony is the wiser leader, as he is able to skillfully navigate and manipulate the complex political climate of Rome while also increasing his own power simultaneously.
Let's compare the two men: Brutus is famous for his honor and nobility, and he ultimately joins the conspirators to protect Rome's republican politics from a tyrannical dictator. These sentiments are entirely honorable and admirable to be sure, but they also illustrate a fatal flaw. Since he is so wrapped up in honor and justice, Brutus naively assumes that other individuals will act with the same selfless attitude. This assumption ultimately proves to be the downfall of both himself and his fellow conspirators. By foolishly letting Antony speak at Caesar's funeral, Brutus inadvertently gives Antony the chance to manipulate the passions of the mob against the conspirators. Indeed, Antony proves to be a cunning politician, as he is able to use carefully crafted rhetoric to influence the masses of Rome and many prominent politicians to turn against Brutus and his companions. As such, though he is less honorable, Antony proves to be the better leader, as he skillfully manipulates Rome's political system to amass personal power.