Oswald wanted historical credit not legal responsibility for his heinous crimes.
That makes no sense unless you're implying that Oswald knew in advance that he would be killed before having his day in court (which allowed the US government to convict him in the court of public opinion without a real trial).
Assuming that he didn't know that Jack Ruby was going to kill him, we can't assume that he had any idea how "history" would view him.
At the time of his death, maybe he believed that he
could beat the charges. That's the only reasonable explanation for his denial of responsibility (assuming he was guilty).
It's not surprising or inconsistent with a political motive that he denied it to the authorities. They were the cops so "let them figure it out" was his motto. Are you really suggesting that photos of the person who is accused of killing the President are not "relevant" when they depict him holding the murder weapon and displaying Commie literature? Nothing to see there? Honestly, that is unreal.
It's only relevant if Oswald expressed anger towards JFK or a dislike of his policies, which he NEVER did despite the Bay of Pigs and Cuban Missile Crisis.
In fact, Oswald told several people including Marina that he
liked JFK and supported his policies on Civil Rights. In other words, there's no indication that Oswald's expressions of Marxist beliefs had anything to do with JFK.
I find it more plausible that the photos were related to Oswald's hatred of General Edwin Walker but that's just speculative and based on the "Hunter of Fascists" caption that was found on George DeMorenschildt's copy of the BYP.
Even most CTers disagree with that since they allege the photos were faked to make Oswald appear guilty (i.e. they were incriminating). Oswald thought he had all the time in the world to come clean. The one card that he still held after his arrest was his confession. He wasn't going to give that up within 48 hours before he even had a lawyer to negotiate a deal to save his hide from Old Sparky.
I accept the authenticity of the photos. I question "who" took them if not Marina, who has given sketchy and inconsistent testimony on the photos.
Beyond that, there's nothing incriminating about the photos. It only becomes incriminating when associated with someone accused of a violent crime.