When Marion Barry was campaigning for mayor, he once boasted to a reporter that when he was elected, he would call a press conference on his first day in office, line up all of the city's department heads that he considered incompetent and fire them on the spot.

Yesterday, when Mayor-elect Marion Barry held his first formal discussion with reporters about the forthcoming Barry administration, the tone was different.

"I'm going to talk personally with these people, look at their economic situation, their job possibilities and other kinds of things," Barry said.

"I'm not interested in putting people on the street without a job, with no place to go."

"On the other hand, I have to have some flexibility to choose the most competent and compassionate person I can find. (But) it's going to be an individual, case by case (process)."

While Barry did not back down on his intention eventually to dismiss all of those on his campaign "hit list" of unfit city administrators, he did say that what he hoped to have in place by Jan. 2, inauguration day, was "the nucleus of a team," not necessarily a whole new administration.

Since winning the general election Tuesday, Barry has begun to muffle much of his hard-line, no-nonsense campaign rhetoric as he comes more and more to grips with the realities of being the mayor-elect and having to deliver on everything he says.

"He has a mayor tone and a mayoral approach, rather than of a candidate," said Florence Tate, Barry's press secretary. "The responsibility is grave now that it's on him."

The old pugnacity of Barry was not gone altogether, however, during the hour-long press conference at which he formally announced the names of members of his transition team and occasionally sparred with reporters to the delight of several dozen Barry supporters.

When, for example, a reporter asked when Barry would establish a talent search process to find persons to fill the top jobs in his administration. Barry responded gruffly and tersely, "It's already set up."

"Who's in charge of that?"

"I am," Barry responded.

Then almost in contradiction, he added, "One of the directions of this administration will not be a one person kind of operation. We're not looking for Messiahs and super-super-super-super kinds of people.

"We're looking for people who can work together in a team, who can be productive, who (are) professional, who (are) competent. And it's a team that's going to solve these problems, with me being the quarterback, the coach and the manager."

The 13-person transition team which may add one or two members will be responsible primarily for telling the new mayor what kind of government he will inherit. It will also advise Barry how best to handle various immediate actions he must take to keep the government going, such as responding to lawsuits, issuing certain orders or developing budget documents within already established deadlines.

The committee, headed by Delano E. Lewis, an assistant vice president of C&P Telephone Co., will also recommend to Barry how best to implachment the various programs and policies on which he campaigned.

Barry sa* id the committee could provide some suggestions on key staff members for the new administration. But he reserved that authority primarily for himself, saying he would be assisted by Lewis and his former campaign manager and longtime friend, Ivanhoe Donaldson.

The steering committee will work Barry said, with 15 task forces, each made up of a cross section of persons of various racial, ethnic, neighborhood, professional and political backgrounds.