Well firstly, Rome did not become “totalitarian”. The word implies there is heavy censorship and control over the minutiae of the daily lives every single citizen. There was no secret police in Rome to police thoughts. Totalitarianism is different to authoritarianism. Rome transitioned to “authoritarianism” because the power of the senate became diluted and transferred much of the power to the caesar or emperor. But the caesar still allow huge degree of freedom and still held sessions with the senate to discuss matters. There is a reason why the Roman empire with an emperor, as its ruler, still lasted for centuries. Many people in the past identified as Romans even long after the Western part fell.
To answer your question, I don’t think much about the Roman empire. I think they’re overrated. They have been the model of many European powers (and the United States) to justify imperialism and colonisation. Rome is being presented as the the force that “civilised” much of Europe from dirty barbarians. That’s not so different from the Western idea of civilising mission and manifest destiny to subjugate dirty indigenous folks in the colonies.