The phrase "a set of ambitious" is correct and usable in written English.
It can be used when referring to a collection or group of ambitious goals, plans, or individuals.
Example: "The organization has developed a set of ambitious initiatives aimed at reducing carbon emissions by 50% over the next decade."
Alternatives: "a collection of ambitious" or "a group of ambitious".
One slide, a bar graph, showed a set of ambitious growth objectives.
Ministers have laid out a set of ambitious targets for green homes.
The European Council agreed a set of ambitious targets to unclog labour markets when it met in Lisbon three years ago.
The Kenya vision 2030 framework (pdf), a set of ambitious macroeconomic, legal, and constitutional reforms, was being implemented in close partnership with the World Bank.
In the year 2000, the world's governments made a historic commitment to a set of ambitious 15-year targets under the umbrella of the millennium development goals.
Having given the All Blacks the hurry up they've shown they have added a set of ambitious backs to the traditional hard-scrummaging pack.
Gupta, wearing tennis shoes with a plant pattern, started talking about his companies, a set of futuristic, ambitious startups that each waver on that knife edge between real and imaginary.
The Obama climate plan also outlines a set of very ambitious international moves designed to reduce emissions globally.
Earlier this year, member states of the United Nations agreed on a set of supremely ambitious goals and targets for sustainable development that leaves no one behind.
At the turn of the century, world leaders came together at the United Nations in New York to develop the Millennium Development Goals (MDGs), a set of eight ambitious goals and targets meant to significantly reduce poverty by the year 2015.
The first is the need to ensure that 2015 ends with a new set of ambitious sustainable development goals and a way of funding them so that they are met.
