I think the New Orleans activity was to create a resume to show the Cubans that he was a friend of the revolution so they'd let him in. Duran said that he showed her much of his work - the Fair Play stuff, et cetera. When he was in the Marines he told Delgado that he wanted to go to Cuba. In the USSR, Marina said he used to sing songs to Fidel and talk glowingly about the "revolution."
Studying the history Cold War has helped me put a lot of this kinds of stuff into context.
It's worth remembering that Castro didn't go full Soviet Communist until after the Bay of Pigs. Prior to the Cuban Missile Crisis, many Americans had a favorable opinion of Castro and the Cuban Revolution. So it shouldn't be viewed as odd or "radical" that Oswald liked Castro in the early 60s.
What seems more odd to me is that Oswald, who supposedly killed JFK because of our policies towards Cuba, told people, including Marina, that he liked Kennedy long after the Bay of Pigs and Cuban Missile crisis. One would expect someone who is so pro-Castro to hate Kennedy as much as he hated Gen. Walker after the Bay of Pigs.
Whatever Oswald's reasons for his admiration of Cuba or Castro, I don't think it was entirely about communism. I think he was just politically ahead of his time as George DeMorenschildt has said. Meaning, Oswald was a few years ahead of the late-60s New Left movements that protested against Vietnam and embraced Marxist philosophy as well as figures like Che Guevara and Castro. If he had not been killed, would he have participated in those movements? Perhaps.
On the otherhand, where were Oswald's communist or marxist friends and associates? It's very difficult to find examples of Oswald associating with people who weren't anti-communists. The Paine's appear to be politically Liberal but nothing about them suggests they supported communism or marxism.
So either he did this on his own volition to impress Havana or he was acting it out for some reason. And that reason was? I don't understand what the purpose of it was for? If Banister was directing him then what was the purpose? And I find it strange that Oswald is out on the street agitating for Castro and then going back and consorting with Banister? And Banister at that time had no connections, as far as I see, with the FBI or CIA. So what was Banister's goal here with Oswald?
I don't think Bannister was Oswald's handler or pulling strings. I'm just noting how absurd it was that he associated with a far-right Bircher like Bannister.
Perhaps someone else was Oswald's handler and placed him with Bannister but that's entirely speculative on my part.
When the Cubans finally approved Oswald's visa weeks after his Mexico City trip, what did he do? Nothing. Strange for someone who so eagerly wanted to go to Cuba.
The only two possibilities are that he was doing those things for
his own personal reasons or he was doing those things
as part of a broader operation that involved other people.
I'll admit that I find the theory that Oswald was part of the CIA/FBI operations against the FPFCC to be a compelling reason for the continuing secrecy surrounding the JFK files. Government agencies might never want to admit to a relationship with the President's would be assassin. Short of covering up their complicity in a conspiracy against Kennedy, covering up their pre-11/22/63 knowledge of or association with Oswald seems like a pretty good rationale.
Lastly, I don' accept much of what Marina told investigators or Pricilla McMillan at face value given Marina's well documented "poor memory"...