The Darling Harbour that emerged from the city-making project that coincided with the nation's bicentenary in 1988, the source of much ambivalence since, was designed as a sort of village. The creators wanted buildings no higher than the 19th century woolstores that lined its shores in the foreshore's days as a loading zone for wheat and wool.

That is about to be upended.

Few will have missed the rising façade on the city's southern edge of a $1.5 billion, much bulkier convention centre mega-complex scheduled for completion in December.

Adjacent to that will be the city's largest five-star hotel, standing 35 storeys and offering 600 rooms, opening next year.

Across Cockle Bay, to the south-east, another major developer has plans to triple the height of the IMAX theatre to 20 storeys with a hotel tower project named for its distinctive "ribbon" shape and which could occupy up to 40,000 square metres.

"It will completely change the area and what Sydney is about," says Philip Cox, the architect behind Darling Harbour's earlier iteration.

Mr Cox laments the "trashing" of a "European" vision, setting the Harbour and CBD on distinctly different scales. The state government is touting the revitalisation of a space to which Sydney has not been connected in the past.

The government notes the new bulk of the convention centre will not come at the expense of public space. In fact the area will increase by a hectare, but it will also bring more locals into an area with strong associations with tourists.

"A new, 20-metre wide pedestrian boulevard will run north-south through the precinct, connecting all parts of [the convention centre] and linking the Darling Harbour waterfront with the south of the city and Central Station," says infrastructure Minister Andrew Constance. "This is truly transformational."

But others suggest  the government's approach is a reminder, in some key respects, of the 1980s approach to creating a "samey" Darling Harbour, which Sydney architect Eoghan Lewis memorably described as resembling a theme park.

The state Liberal government launched into the project soon after its election in 2011. The manner in which it did so, argues City of Sydney councillor and urban planning expert John Mant, followed a similar pattern to the earlier development: a government authority did a deal with a developer, giving them free rein over swathes of land in exchange for new public facilities.

"The easiest way to do it is to have a single developer with deep pockets do everything," says Mant. "But the result is that the whole of the western side of the CBD is Lend Lease-ville.

"And when you give one developer a monopoly right as leasing manager, he's only going to be judged on the profits returned. He's not going to take a chance on an exciting new restaurateur or coffee shops that aren't Gloria Jeans."

Indeed, Lend Lease and partners have won about $3.5 billion projects in the area, through, the state government notes, a competitive tender process to enact the government's vision for the area.

The multinational will build not just the convention-entertainment-and-exhibition centre complex opening this year but also "Darling Square", a nearby new neighbourhood with thousands of apartments and retail space – opening in stages up to 2020. It also has won the contract for the Sofitel next door. The combined value of the projects is $1.9 billion.

Shaun Carter, the President of the Institute of Architects, argues the new Darling Harbour will rise on the bones of whatever heritage was to be found in the area's first design.

The previous exhibition centre, which won Mr Cox the Institute's Sulman prize for architectural excellence, has been torn down for the mega-centre.

And the opening of the new redevelopment will coincide with a decision to remove the Powerhouse Museum from the entrance to Darling Harbour. The site will potentially be sold and the museum moved to Parramatta.

"I'm not sure what the outcome will be," Mr Carter says. "I'm not sure a whole lot of people do."