Unusually for a production featuring the death of Caesar, he does not utter his famous last words "You too, Brutus?". This is because the showrunners based their depiction of Rome on the writings of historians of the time such as Plutarch and Suetonius, who stated that Caesar said nothing when he died.
Cicero's protests at Vorenus being elevated to the senate despite being a Plebeian are hypocritical. In fact, Cicero himself was originally a Plebeian. Indeed, many senators were plebeians, including Marc Antony.
During Caesar's assassination, Cassius says: "Thus always for tyrants!". This is the literal translation of the Latin phrase "Sic semper tyrannis", which was also used by John Wilkes Booth when he killed Abraham Lincoln.
The Ancient Roman Suetonius recorded that had Caesar lived, he had planned to enact a series of public works, drain the Promptine marshes, triple the size of all libraries, and build a highway from the Tiber River through the Appenine Mountains to the Adriatic Sea.
When the child is put to bed, he is addressed as "little man". The Ancient Romans didn't actually have the word "child" in their vocabulary. So children were referred to as small adults.