There is "next-to-no public appetite" for radical change at the BBC, the chairman of the broadcaster's governing body has said.
In a keynote speech at the Institute of Directors' annual dinner, BBC Trust boss Rona Fairhead said the BBC was the "beating heart" of the UK's creative industries - but can and should do more.
The BBC's Royal Charter, due to expire in 2016, is currently under Government review, and Culture, Media and Sport Secretary John Whittingdale sparked fears the BBC would be scaled back when he said the review would look at whether the broadcaster should continue to be ''all things to all people'' or have a more ''precisely targeted'' mission.
Ms Fairhead highlighted the "pivotal contribution" made by the BBC to the "Darwinian success story" of the UK's creative industries.
She said: "I'm not here tonight to defend everything the BBC has done in the past, nor everything it will do in the future.
"It is not perfect and changes will need to be made, and we must be clear about where those changes need to be made.
"For example, the BBC must become ever more efficient and agile to ensure the best possible value for money; and it needs to have a simpler, more accountable governance structure.
"But the BBC plays a central, critical and unrivalled role in one of the big business success stories of the 21st century - the UK's creative industries.
"It's a shared success story, but the BBC is its beating heart. But that doesn't mean the BBC cannot do more. The BBC can and should. It needs to be a better partner for the rest of the creative and cultural sector."
One way of doing that was to include a "sharper, more distinctive remit" for the BBC set out in the charter to explicitly describe what the BBC exists to achieve, she added.
"But our overall goal should be one of evolution, rather than revolution.
"There is next-to-no public appetite for radical change in the BBC. People want the BBC to be nurtured, rather than subject to root and branch reform.
"Changes should be specific and targeted, rather than sweeping and grand.
"The global achievements of the UK's creative industries are a Darwinian success story in which the BBC has made a pivotal contribution.
"We should continue to help that success story evolve, not change the whole environment it has thrived in," she said.
Ms Fairhead said the trust has had an "unprecedented" response to its public consultations, with tens of thousands of people giving their views on the BBC.
"They show a truly humbling degree of trust in what the BBC tells them. They recognise that it's a unique institution. They show it enjoys extraordinary levels of support and that they are willing to pay for it," she said.
She referred to the BBC Introducing website, which allows any UK musician to upload their material.
"The best gets airtime on BBC local radio and the best of the best are invited to play live on BBC Introducing stages at major festivals.
"That's how Jake Bugg and Ed Sheeran got their big breaks," she added.