Philippus never had much of an interest in young Octavius.
Augustus dramatically enlarged the Empire, annexing Egypt, Dalmatia, Pannonia, Noricum, and Raetia; expanding possessions in Africa; expanding into Germania; and completing the conquest of Hispania.
Beyond the frontiers, he secured the Empire with a buffer region of client states and made peace with the Parthian Empire through diplomacy.
After the demise of the Second Triumvirate, Augustus restored the outward façade of the free Republic, with governmental power vested in the Roman Senate, the executive magistrates, and the legislative assemblies.
In reality, however, he retained his autocratic power over the Republic as a military dictator.
Mark Antony was amassing political support, but Octavian still had opportunity to rival him as the leading member of the faction supporting Caesar.