HAVANA — Now that Fidel Castro has retired, many Cubans are looking to his brother to let more people open businesses, own homes, and even travel abroad. But it will probably fall to a new generation of leaders to ultimately fulfill or frustrate their dreams of prosperity.

During his 11⁄2 years as acting president, 76-year-old Raul Castro has hinted at reform but made few major changes — a reticence many see as a sign of respect for his beloved, more doctrinaire older brother, who survived despite the efforts of 10 American presidents to bring him down.

And while hoping that Raul Castro and his likely no. 2, Carlos Lage, will advocate for change, they wonder how that will fly with Fidel Castro, who stepped down but isn’t going away.

“There has to be some change, more freedom with Raul,” Andres, 63, who like many Cubans wouldn’t give his last name, said. “The other one always nipped that off at the bud.”

The resignation, announced today, should give Raul Castro the autonomy he lacked as the government’s caretaker since Fidel Castro was sidelined by intestinal surgery in July 2006.

The younger Castro raised expectations of openings in the state-controlled economy with his reported fascination with Chinese-style capitalism, calls for unspecified “structural changes,” and acknowledgment that government wages averaging $19 a month do not satisfy basic needs. He also encouraged Cubans to open a fearless and critical debate, as long as they remember that the final decisions will be made by the island’s Communist leaders.

“That way we reach decisions, and I’m talking about big decisions,” he told student leaders in December 2006.

Many Cubans want to hear more such talk from their next leader. Inspired by Raul Castro, some leading Cuban cultural figures have called recently for dropping onerous visa requirements and other limits on their freedoms, a message that resonates with ordinary Cubans.

“This is what we needed. I hope to God people have more freedom — the freedom to have opinions and always speak their minds,” 37-year-old Lydis Perez said after dropping her son off at school. “People talk in the hallways or the back rooms. … There’s a lot of fear.”

Fidel Castro, however, insisted in his resignation letter today that he won’t disappear — or stay quiet if he sees his revolution going astray.

“This is not my farewell to you,” he wrote. “My only wish is to fight as a soldier in the battle of ideas. I shall continue to write under the title, ‘Reflections of Comrade Fidel.’ It will be another weapon you can count on. Perhaps my voice will be heard.”

As the Council of State’s first vice president, Raul Castro has been his brother’s constitutionally designated successor for decades, so the big question is who will take his place as no. 2 on Sunday when the National Assembly selects Cuba’s new leadership.

A leading candidate is Mr. Lage, the de-facto prime minister, who at 56 is a full generation younger than the Castros. He’s among the most experienced leaders in a power structure dominated by septuagenarian former rebels, and he has built a reputation as a reformer.

A less likely possibility could emerge from a handful of leaders in their 30s and 40s, such as Foreign Minister Felipe Perez Roque, whose Communist fervor earned them the collective nickname of “Young Talibans.”

While no less loyal to the elder Castro, Mr. Lage was the architect of reforms that saved the island from economic collapse in the early 1990s. His moves allowed foreign investment in state enterprises, a measure of self-employment, and legal use of the American dollar.

Raul Castro appears to get along with Mr. Lage, who is a quiet, pragmatic organizer like himself. Raul Castro backed Mr. Lage’s earlier reform proposals, especially farmers markets where excess crops are sold at market prices.

But both Mr. Lage and Raul Castro say any change will not be at the expense of socialism. And Mr. Lage has dampened hopes that Cuba would follow China and Vietnam in allowing capitalist markets to thrive.

“Their successes and failures should enrich our efforts,” Mr. Lage told managers of state enterprises last year. “But the building of socialism in Cuba is only possible as a result of our own experiences.”

Raul Castro also has championed the concept of closer ties to America, offering again and again to discuss normalizing relations with Washington. But the Bush administration ruled that out today, deriding Raul Castro as “Fidel Lite.”

That means that the nearly five-decade American embargo of Cuba will remain in place for the known future — frustrating both Cubans and many Americans who see much potential in trade with the island, not only for business but as a catalyst for change.

And despite a detailed American plan meant to encourage a “democratic transition” from the Castros’s rule, Cuban officials insist the island’s socialist political and economic systems will endure.

For now, that means Cuba’s tiny dissident community can only wait, and hope that the new leadership will be more open to change from within.

“History will say if it is a good day,” Oswaldo Paya, whose Varela Project seeking a referendum on civil rights and electoral reforms was quashed under the elder Castro’s rule, said.