Bring on the tough stuff - there’s not just one right answer.
Is Cassius responsible for turning Brutus's thoughts to murdering Caesar? That's usually the claim, but we know that Brutus is vexed by some personal issues before Cassius even brings up the idea of murder. Is there any indication in the play that Brutus had already been thinking about killing Caesar? Why would he?
What type of ruler does the average Roman citizen in the play want? A king? An arrogant and confident ruler? Someone who uses reason and acts honorably?
Women seem kind of superfluous to this play. Even Brutus, who loves Portia, seems to treat her unkindly. Could this whole tragedy have been avoided if the women had been heeded? Why is what some might call "woman's intuition" dismissed in the play as cowardice and foolishness?
From the very first time Antony meets with Octavius and Lepidus, it's clear that he lacks loyalty. He starts trash-talking Lepidus as soon as the guy leaves the room. In historical reality, these three men did join together to lead Rome and later broke up and turned against each other. In the play, many of Rome's powerful men feel no shame about betraying or lying for their advantage, usually under the cover of the national good. Was this just a natural and accepted part of power, or did the triumvirate that replaced Julius Caesar really think they would be honorable to each other? Is this addressed in the play?
Rhetoric is an important part of the play, as it was in ancient Rome. Much of the main action in the play relating to treachery is never even spoken – everyone involved is persuaded by veiled and cautious words. Is this because the rhetoric of the time was so powerful that people didn't know they were being manipulated, or did they secretly agree with the subtext of betrayal? Does rhetoric work the same way now? Have people changed that much with regard to how they hear their leaders and interpret their own fears?