How was the Roman Republic transformed under Augustus and the Good Emperors after him?
August transformed the republic by keeping it in tact outwardly. All the existing offices remained fully in tact. The difference being that he decided who would fill it. Not the electorate. In fact, he never ever said he started an empire with himself as emperor. The good emperors came quite a bit later, when Rome was an empire for well over a century. The republic was a relic from the past. The good emperors filled most positions with the second level of society: the knight class. For several reasons: many of the old noble families had died out; there weren’t too many old noble families left to fill all the vacancies. The knight class provided badly needed new blood. By then, it was more acceptable than under Augustus.