But in a Web forum on the site of Juventud Rebelde (Rebel Youth), one of the two main state-run daily newspapers, Cubans this week got a glimpse of what the changes might entail, with readers asking openly for direct election of the country's top leaders and the ability to remove them through a recall vote.
To be clear, the readers' questions do not amount to a formal announcement, and the responses to them by Cuban election officials revealed little.
Yet the mere publication of such proposals in Cuba's tightly-controlled state media is remarkable, and not likely a coincidence. Questions and comments from readers on Cuban government sites are carefully filtered, if not planted by editors and party loyalists.
There were several queries like this: "I'd like to know if the possibility of a direct vote for the top leadership positions in the country is under consideration," asked reader "GCR," who added that "the current system is (in my view) highly unpopular."
President Raúl Castro has set the next Communist Party Congress for April 2016, and the events are typically the occasion for reform announcements. With Castro, 83, saying he'll step down in 2018, next year's meeting would, in theory, set the stage for the formal transition to a post-Castro era.
Next in line to succeed Castro is Cuba's first vice president, Miguel Diaz-Canel, 54.
Under the existing, complicated electoral system, Cubans vote among pre-screened parliamentary delegates who in turn elect the government's top executives, with a Castro always at the helm. There are no political parties, no public debates and no dissenting views. No other political model in the hemisphere is so rigid.
And with U.S.-Cuba tensions easing, Raúl Castro may see a narrow window to make major changes while he and his brother Fidel, 88, are still alive.
Some of the reader questions in the forum seem unprecedented in state media. One reader wanted to know about mechanisms to remove the president or vice president through a recall vote "even before their term is complete." Another commentator, listed as Carlos Gutierrez, asked for direct elections and for Cuba's parliamentary sessions to be broadcast live on radio and television.
It is possible that such queries reflect nothing more than a decision by Juventud Rebelde's editors to opt for less censorship and more open engagement. But that's unlikely in a country where so little is left to chance.
Raúl Castro has repeatedly insisted that the changes to Cuba's system he's implemented are in response to pressure from below, and this type of Web forum may be a way to create a perception of democratic give-and-take.
After a near-fatal illness forced his older brother aside in 2006, Raúl Castro organized public debates in Cuban neighborhoods about the country's economic model, then presented the reforms that followed -- "updates" is the official term -- as an expression of popular will.
With the Cuban parliament preparing to return to the long-abandoned halls of the Havana Capitolio as soon as this year, there have also been rumors that the 600-or-so-member body will be downsized and its seats earned through more competitive elections.
Raúl Castro has already proposed term limits for top leadership positions in the government, which his brother ran for 47 years.
Such changes, and even a few of the ones floated in the Web forum this week, would not make Cuba a multi-party liberal democracy overnight. But they would, without a doubt, represent the most important overhaul to Cuba's ironclad political system in decades.