Augustus

I think Augustus was a more important leader than Caesar because of his development of Rome.  Although Caesar made the initial reforms to Rome, he was also a dictator and was not liked by many of the people  Augustus, however, gave Rome many great buildings like the Altar of Peace, many temples, and the Forum.  He also developed the Roman Baths which improved the water system to the city.  
 
Instead of using politics which divided people for or against Caesar, Augustus used the buildings to strengthen the monarchy.  For example, he built the Altar of Peace to remember the peace he brought to Rome, and by give Caesar a temple, which was making him like a God.  This meant that Augustus also had this status.  All these treasure, strengthened Rome as a great city and Augustus avoided being murdered like Caesar.  These things made Augustus a more important leader.