Did Oliver Stone tell us everything we need to know? I feel like the administration made a big deal of making sure the papers were released on the 25th anniversary, but nothing after that.
While I certainly hope you were being glib with your Oliver Stone comment, the short answer to your question is: "Not much." There certainly was no information that changed the official narrative of the assassination; though there were a lot of intriguing new bits of information about the case, and semi-unrelated cases.
The Washington Post did an absolutely terrific breakdown of the most notable revelations here:
Probably the most notable, at least from my perspective, were documents detailing some of the various CIA plans and plots to kill Castro. This, of course, has long been known, but this particular document (the first one listed in the Washington Post piece) is an official 1975 internal examination of all the efforts and fleshes out the various plots in much greater detail than was ever known before.
The 82 page memo refers to another, unpublished 1967 memo by J. Edgar Hoover with the absolutely wonderfully title of "Central Intelligence Agency's Intentions to Send Hoodlums to Cuba to Assassinate Castro." This, of course, speaks to the intra-agency conflicts between the FBI and the CIA on matters related to Cuba.
But your question is "is there anything in these files that provides any type of indication of a conspiracy in the JFK assasination?" and the answer is, "No." The whole release dominated the news cycle for what, about a day? The level of revelations--dominated by interesting but not particularly revelatory minutiae--seems to indicate that this was about the appropriate level of general interest.
Keep in mind that at the very last moment, Donald Trump elected to withhold numerous documents for further vetting. So until those specific documents are released, we are looking at a subset of all of the information still contained in the archives.
I have a related question, given a large information dump like the JFK investigation, how do historians analyze the information these days?
Perhaps nothing new in the US, but the released papers revealed and confirmed how deep was the involvement of the CIA with the Mexican government, and we are talking about presidential involvement, Harvey Lee Oswald and spying the embassies and communications from Soviet aligned countries in Mexico.
The papers, specially some telegraphs, confirmed the identities of LITENSOR, LITEMPO-8 and LITEMPO-2, code names for the Mexican president at the moment Adolfo López Mateos, former president Luis Echeverría, and Secretary of state Gustavo Díaz Ordaz (Who would become president the following term) respectively.
The telegraphs had a thorough description of Harvey's Lee Oswald activities in Mexico before JFKs assassination, and the communications held between all the possible actors specifically between the Cuban and Russian embassies in Mexico City.
If the identities of the spies were outrageous, the president and top political actors, and a sovereign country working for a foreign entity.... the fact that they were under the CIA payroll was, with their names and amounts detailed, ... just too much. Those papers were meant to be released around 1994s but the US Commission in charge of that put another 15 years of reserve to the documents. It's believed that it was an arrangement between the Mexican ruling party at the moment PRI and the CIA, as the elections were around the corner with the ruling party at that moment being the same as the one in the 70's. In addition, treason (aiding a foreign country) is the only crime for which a (ex)president can be held accountable for by the Mexican justice.
This is just the tip of the iceberg. The involvement of Mexican senators, governors, chiefs of police and presidents is starting to be confirmed. A good starting point in English could be Inside the Company from Philip Agee.
Source 1 in Spanish
I'm curious, is there a way to make sure released documents haven't been modified?
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