The choice of his cabinet members pick has been defended by Donald Trump as he meets Ohio victims.
The 70-year-old president-elect, who has never previously held elective office, on Thursday announced Oklahoma Attorney General Scott Pruitt, a climate skeptic, as environment chief and fast food executive Andy Puzder as labor secretary.
More than half his cabinet positions have now been filled, 43 days before the Republican is sworn in as the 45th president of the United States, the oldest man ever inaugurated into the office.
"I believe we're in the process of putting together one of the great cabinets that has ever been assembled in the history of our nation," Trump told a victory rally in Des Moines, Iowa.
It was the third of his unorthodox "thank you" rallies feting his shock electoral defeat of Hillary Clinton in key swing states that have propelled him into the leadership of the most powerful democracy on earth.
"In filling my cabinet I'm looking for people who fully understand the meaning of service and who are committed to advancing the common good," he added, defending his appointment of a string of billionaires and millionaires.
His nominees, he said, had given up fortunes "to make one dollar a year," hailing them as "talented people, smart people."
The incoming president triggered criticism by tapping a fossil fuel industry ally to head the Environmental Protection Agency (EPA) -- outraging many who fear that he will reverse President Barack Obama's efforts to combat climate change.
"We're going to end the EPA intrusion into your lives," he told the Iowa crowd.
In announcing the nomination of Pruitt -- who will need Senate approval -- Trump complained that "for too long," the EPA had spent "taxpayer dollars on an out-of-control anti-energy agenda that has destroyed millions of jobs."
Steny Hoyer, the number two Democrat in the House of Representatives, said Pruitt had spent years "fighting tooth and nail to help polluters erase or circumvent the critical environmental protections our nation has put in place."
Ken Kimmell, president of the Union of Concerned Scientists, described Pruitt as someone "on the outer extreme edge, and putting him in charge of EPA could really have devastating consequences."
The appointment was made despite Trump's meeting this week with former Democratic vice president-turned-climate campaigner Al Gore and actor Leonardo DiCaprio, who is an active environmentalist.
There was similar uproar over his nomination of Andy Puzder, CEO of CKE Restaurants which owns fast food chain Hardees, as secretary of labor.
Puzder opposes a Democratic Party push to raise the minimum wage to $15. In a Wall Street Journal op-ed this year he backed increasing use of automated technology instead of workers to keep down labor costs, complaining about the $15 wage, mandatory paid sick leave and the burden of Obamacare for employers.
"The president-elect believes, as do I, the right government policies can result in more jobs and better wages for the American worker," he said Thursday.
"Trump has once again shown how out-of-touch he is with what working Americans need," hit back Service Employees International Union head Mary Kay Henry, whose organization has two million members.
"We will stay in the streets to fight back against anti-worker extremism."
In a move that fanned concerns about his conflict of interest as a business tycoon, Trump is to stay on as executive producer on NBC's "Celebrity Apprentice" when it returns after a two-year absence, the show confirmed.
The real estate tycoon has promised to set out a plan next week to put aside his "great business in total," although he has not revealed who will take over his multi-billion-dollar global property and luxury branding interests.
"One of the most important relations we must improve and we have to improve, is our relationship with China," Trump said.
He flew in from Ohio, another state which helped secure his victory, to meet privately with victims and first responders of an apparent jihadist-inspired November 28 attack at Ohio State University.
The assailant, Abdul Razak Ali Artan, was shot and killed by police after driving into a crowd and then slashing several people with a knife. Officials said 11 people were treated for injuries.
"This horrific assault is yet one more tragic reminder that immigration security is now national security," he said later in Iowa.
Last week he tweeted that Artan, who migrated from Somalia, should not have been in the country.
At least one of the victims refused to attend. Professor William Clark told CNN that he didn't feel the need from a "healing standpoint" and that he was "frankly a little put off" by Trump's initial reaction in blaming immigration.