'As a party member, I will work hard and teach other people how to get rich together and let more people benefit by getting rich," Wang Dongxin said as hundreds of Communist Party members swarmed into Beijing's Great Hall of the People to hear Chinese president Hu Jintao deliver a landmark speech.

Wang is the general manager of Jiangxi Luhuan Animal Husbandry, a pig-breeding company founded in 2003 which has grown to now employ nearly 400 people in the eastern province of Jiangxi. Like a growing number of party members, the provincial "model worker" and entrepreneur is already rich.

"My personal feeling is that life is getting better and better," Wang said.

As Wang and the rest of the 2268 delegates to the party's crucial five-yearly congress listened inside the vast, Soviet-style auditorium a few minutes later, Hu gave his final major speech as party leader before he hands power to Xi Jinping, currently vice-president, on Thursday.

Hu, 69, said he left behind a decade of "historic successes" including double-digit economic growth and "steady improvement in democracy". China will pursue scientific development, promote social harmony and improve welfare for its 1.3 billion people over the next decade, he said.

Hu's "scientific outlook on development" is already enshrined in the party's constitution, cementing its place alongside the ideology of previous leaders Mao Zedong, Deng Xiaoping and Jiang Zemin. The "scientific outlook" underpins the party's efforts to rebalance the country's economy by shifting focus away from its long reliance on exports and investment in infrastructure. It promotes domestic demand, environmental protection and sustainable development that benefits poorer regions.

In classic Marxist language, Hu said China was still in the "primary stage of socialism" and still needed to pursue "socialist modernisation" as its main task, aiming to double the 2010 per-capita income of both urban and rural residents by 2020. Hu has previously said China's modernisation drive under one-party rule would take "several, a dozen or even dozens of generations".

His speech gave the latest signal that the party will prioritise economic development and will not move towards multi-party democracy or direct elections of its leaders. Hu said China would "never copy the model of Western political systems", while state media warned of the "turmoil" caused by rapid democratic change in Russia, Latin America and Africa.

"I think China's political reform should follow Chinese social characteristics," Wang said at the congress.

The party opened up the economy from the early 1980s under Deng, who died in 1997, introducing a policy to "let some people get rich first".

Many of those who enjoy the fruits of 30 years of partial economic liberalisation are former colleagues, friends and relatives of current and past party officials.

Founded in 1921, the party has ruled for 63 years since Mao proclaimed the founding of the People's Republic of China in 1949. Once dominated by workers and farmers, the party changed its constitution in 2002 to cement Jiang's policy of enlisting "new forces", especially entrepreneurs like Wang. It has expanded rapidly to more than 82 million members. Its 3.9 million branches reach everywhere from nightclubs to foreign multinationals, but many people are attracted more by business and personal connections than ideology.

Jiang, 86, returned to the limelight at the congress, sitting close to Hu during a live broadcast of Hu's speech by state TV. Wu Qiang, a political scientist at Beijing's Tsinghua University, said Jiang remained the party's second most powerful leader behind Hu. The two men, plus Xi, are the leading figures in intense negotiations behind the scenes over the party's future leaders and the direction of its economic and political reforms.

Xi, 59, and vice-premier Li Keqiang, who is expected to take over from Wen Jiabao as state premier in March, are certainties for membership of the new Standing Committee, to be named on Thursday. However, doubt still surrounds the remaining seats – and even how many seats there will be.

About 70% of China's party, military and state leaders are expected to change by early next year, meaning the leadership transition will probably be the largest for 30 years. Beijing-based political commentator Zhang Lifan said: "I think this is the tensest party congress since 1989."

In 1989, party leaders were divided over how to handle widespread democracy protests that were eventually crushed when the party sent troops to clear Beijing's Tiananmen Square. The divisions were reignited this year by the scandal surrounding deposed regional leader Bo Xilai, a populist once tipped for a top leadership post. Bo awaits trial on charges of corruption, abuse of power and covering up the murder of British citizen Neil Heywood by his wife, Gu Kailai.

Concerned observers and mainstream party members claimed Bo and powerful allies in the military and security forces had lobbied for more influence, potentially undermining the party's succession plans. Bo's downfall "saved China - from heading down an ultra-left route," said Hu Xingdou, an economist and liberal political commentator.

But the scandal over Bo reinforced a public perception of widespread corruption and nepotism among party officials. In another blow, Bloomberg News reported in June that Xi's extended family had accumulated assets worth hundreds of millions of dollars during his rise, though the agency did not allege that corruption was involved. And the New York Times reported last month that the extended family of Premier Wen Jiabao, once seen by optimists as China's best hope for political reform, had amassed assets worth $2.7 billion.

Hu used his speech to urge officials to strengthen "supervision over their families and their staff". The fight against corruption is a "major political issue of great concern to the people," he said. "If we fail to handle this issue well, it could prove fatal to the party."

But Hu Jia, a leading rights activist, said Hu's speech and remarks by Xi at the congress were full of "hackneyed phrases". He said the highly orchestrated congress was "completely an 'emperor's new clothes' show".

Hu Jia and scores of other dissidents and activists were detained, threatened or held under house arrest in what rights group Amnesty International said was a "intensifying crackdown" in the run-up to the congress.

Hu Jintao's decade in power left many inside and outside the party disappointed. Zhang Ming, a political scientist at People's University in Beijing, said many economic problems had accumulated because of slow reform, including huge income gaps, regional differences, conflicts between officials and the public, and poor health care. "It's a lost decade. It's the Brezhnev era," he said, referring to stalled economic reforms in the former Soviet Union under Leonid Brezhnev.

Like Hu, Xi could prove more Brezhnev than Gorbachev, although optimists still hold some hope that he may become bolder once he consolidates his power base.

Known as a "princeling" because he is one of several prominent current leaders who are the sons of former top party members, Xi is married to People's Liberation Army singer Peng Liyuan. But until he reached the Standing Committee in 2007, most Chinese knew Xi's father and his TV-star wife better than the leader.

While trying to maintain the economic growth that gives the party its public mandate, and overseeing gradual political reform, Xi will have to negotiate shifting regional and international power balances. In another sign of the internal problems he faces, six more Tibetans set fire to themselves to protest about Chinese rule on Wednesday and Thursday, escalating a campaign that has seen about 70 self-immolations in the past two years.

China's party and military leaders were concerned by the recent US strategic pivot to the Asia-Pacific region, but in a message congratulating Obama on his re-election, Hu said the world's two largest economies were "constructing a new model for relations between great powers".

However, Hu's congress speech urged the People's Liberation Army to "build China into a maritime power" and develop the capability to "win a local war in the information age", comments that could worry Japan, Taiwan and China's south-east Asian neighbours.

State media have run a three-month campaign backing China's claims to the Japanese-controlled Senkaku, or Diaoyu, islands. And a congress delegate from Sansha, an offshore district set up in June to administer most of the South China Sea, is promoting tourism near islands disputed with Vietnam and the Philippines.

Yet a smaller, friendlier south-east Asian nation could help the party maintain its grip on power while spreading the benefits of its prosperity and conceding more political ground.

Several recent state media reports discussed how China could learn from a "Singapore model" of governance. A recent paper by the state-run journal China Reform said Singapore had succeeded in building "weak democracy under the rule of law". It advocated China building "Singapore-style rule of law" over the next decade.

In another sign that the party is about to revive the Singapore model, which was praised by Deng and Jiang, state-run China Central Television is producing a series on the merits of the city-state, according to reports by Singapore's Straits Times, to be broadcast in early 2013.

Developing Singapore-style economic and political control of hundreds of Chinese city-states could buy time with China's affluent middle-class and it could also appease millions of rural residents – but it would not satisfy China's growing number of outspoken dissidents.

US-based Citizen Power for China issued a pre-congress appeal for democratic reform in an open letter that it said was drafted by leading Chinese writers, lawyers, scholars and rights activists.

Exiled dissident Yang Jianli, a close friend and supporter of jailed Nobel Peace Prize winner Liu Xiaobo, said the names of dissidents were withheld to "protect them from further retaliation and repression".

The letter accused the party of reneging on promises it made to develop democracy and warned that delaying reforms could lead to disaster.

"We want to fight and sacrifice to leave a most precious gift to our children: a free and democratic China governed by rule of law," the dissidents said.