Mark Antony was no way inferior to Agrippa in military talent (the only direct confront between them, at Actium, was in truth a win by Antony who was able to break the naval siege of Agrippa and escape with the bigger part of his fleet). Agrippa was loyal to Octavian sure but still was not Octavian himself and Antony in 44-43 mostly undervalued the ambition and arrogance of Octavian but many other people made the same mistake including the super experienced politician Cicero (who helped a lot Octavian against Antony in that period, by the way thinking who Antony was dangerous and Octavian inoffensive)...
Antony also was good in that (before being destroyed by Octavian's propagand) and was much respected by his peers and his tentative to keep the peace in Rome in the confusion who followed the death of Caesar was good and great as without him and his woprk a bloodbath would have been inevitable (as it had already begun) and the consequences would have been likely disastrous for both sides. Octavian was much more ruthless than him, noncurant of anything but his ambitions and a master in propaganda and had the big lucck to have a friend like Agrippa who was great in the exact thing he needed the most
And for ruling Rome in that period you needed to be great in politic but also on the field
Augustus career would show the opposite. He was terrible in the field, but was the greatest Emperor of Rome.
Antony was a fool because he made Octavian an enemy by refusing to give over Caesar's money that he kept when Octavian first applied to him as Caesar's heir. That doesn't require underestimating Octavian. That only needed Antony being faithful to Caesar's will. Every misfortune that happened afterwards sprang from that decision.
Octavian then realized Antony was his enemy, and would not give Caesar's fortune to him without a struggle. Then of course, Octavian appealed to the people of Rome and of Caesar's veterans complaining of Antony's treatment of him, that brought Octavian his first following. So he needed Caesar's partisans and clients to win his struggle with Antony.
Of course, that undermined Antony's position as a moderate consul who brokered a compromise. Now, to Caesarians, he seemed a traitor who let go of the assassins. And Antony's conduct towards Octavian alienated a lot of legions, and several declared for the heir of Caesar.
So Antony had to do acts to win back the adherents of Caesar who was going to Octavian because of Antony's actions towards Caesar's heir. But those acts would alienate the moderates and the Republicans in the Senate.
But that was not enough to bring the Senate against Antony. It needed something to make them think that they can win.
So they turn to Octavian. But why? Why trust a callow 18 year old? Who was anathema to all their principles, and who was now illegally recruiting an army.
Enter Cicero. And it wasn't just chance. Ever since Octavian entered Italy after the assassination, Octavian cultivated the great orator. He visited him regularly, he wrote to him for advise, etc. so much so that despite his misgivings, Cicero began to think of Octavian as a protoge, a useful tool, despite the fact that everything about Octavian should have made Cicero wary.
So Octavian and Cicero made a pact. Cicero would legalize Octavian's position, and Octavian would join his legions with the legions of the Consuls Hirtius and Pansa and become the humble servant of the Senate, and by extension, Cicero.
Meanwhile, Antony went to Cisalpine Gaul to claim the province from Decimus Brutus, who Antony approved as governor in the aftermath of the assassination. Of course, Decimus refused. Why should he give way to Antony? So Antony besieged him in Mutina.
Octavian then became co-commander with Hirtius and Pansa in the Mutina campaign...
Just looking at the events would show that Antony really was outmaneuvered, outwitted, etc by a 18 year old boy would show either that Antony is a utter dunce of a politician, or that Octavian is a really good politician, far better than Antony.
As for Agrippa, Octavius made him his friend and follower before Caesar's assassination. Being utterly sickly, he knew he would not be a good soldier, so he made friends with a provincial nobody, Agrippa, who was of the same age of him, who would fight for him.
That shows that he knew how to select his friends and subordinates, estimate their talents, and use them, even before he even became Caesar's heir.
As for propaganda, it's part of politics. After all, you need propaganda to win friends, and detach the supporters of the other side. Losing the propaganda was really shows' Antony's ineptness as a politician. He, a far better soldier than Octavian, could lose the propaganda war really shows something.
As for Agrippa and Antony, Agrippa is better. Actium is Agrippa's campaign, and for Antony a very winnable war.