For those who feel confused, frustrated and a bit disappointed because the field of candidates for next year's mayoral race seems like the "same old stuff," Ronald H. Brown is rather pointedly volunteering to be the fresh face - the "Jimmy Who?" - of 1978, who can inject new blood into city politics and government.

"I sense there is a reaching out, a yearning for new leadership in this city, and people who talk to me are trying to convince me that that new leadership should be me," Brown said over lunch the other day. "I see no reason for anybody to rush to judgement. We've got 10 months or more before the primary. If I were advising citizens, I'd tell them to hold put for a couple fo months. I see no advantage - except to the three 'out front' candidates - of choosing up sides now."

Many citizens, businesspeople and even a few politicians are quick to say privately that with Mayor Walter E. Washington, City Council Chairman Sterling Tucker and City Councilman Marion Barry as the only persons available so far, a sorely needed choice on the 1978 mayoral ballot is "(d) None of the above."

Brown, 36-year-old lawyer who is deputy executive director of the National Urban League, was born in Washington, D.C., and grew up in New York City. If that begins to make him seem a little bit like the last new-look mayoral contender, former Equal Employment Opportunity Commission Chairman Clifford L. Alexander, it's not necessarily coincidene. Brown and Alexander - who is now secretary of the Army - are "very close personal friends," and many of those who backed Alexander's near-successful bid against Washington in 1974 are among those urging Brown to run in 1978, Brown says.

Like Alexander, Brown is a nearneophyte in local politics. He has never served in an elected position in city government and, though he is a Democrat, is not active in the city's Democratic Party. But for the past year, he has been chairman of the board of the University of the District of Columbia (elected chairman by his board colleagues). It is in that role, Brown believes, tht he has paid a bit of D.C. dues. And as a result of his work on the board, he contends, he will be less vulnerable to one major political albatross borne by Alexander, namely the accuuation of being an outsider.

Brown believes that running the national programs for the Urban League and being its principal lobbyist in Washington have helped him to establish a certain national reputation that would give new prominence to the mayor's office in the District.

"Do you think the president would call Walter Washington on urban policy? He'd call me on urban policy," Brown said. (For the record, neither one has gotten a call from the White House on urban policy)

Brown is softly blowing his own political horn these days hoping that once the word gets out that he's available, some folks will take interest. But in some cases, he may have to do a little more blowing before anyone's mind is made up.

"I know Ron Brown, but I don't know that I know him that well," said Foster Shannon, outgoing president of the Metropolitan Washington Board of Trade.

"I would say that if he announced he was going to run for mayor, I would stop and want to take a good look at him," said realtor Flaxie Pinkett, the longtime friend and supporter of Mayor Washington.

At this early stage, Brown's major rival for being the widely sought new face is John Ray, who announced his candidacy several months ago. The Rev. David Eaton of All Soul's Unitarian Church is still undecided but leaning away from the mayor's race, sources say. And former Department of Housing and Urban Development Assistant Secretary H.R. Crawford is expected to run as an at-large candidate for the City Council.

It's nice to have acquintances in important places, and maybe that's one thing that's helpful to the Legislative Fiscal Bureau of the Metropolitan Washington Board of Trade when it deals with the City Council.

The manager of the bureau is Jerry A. Moore III, the son of the Council's lone Republican, Jerry A. Moore Jr. The vice chairman of the bureau is lawyer Robert B. Washington Jr., the chairman of the D.C. Democratic State Committee. Eleven of the 13 persons on the Council are Democrats.

Washington appears to have done some of the planning in the trade board's successful assault on a proposal by Council member David Clarke that could have created two property tax rates in the city instead of the present one, with a higher rate for businesses.

After what Clarke publicly termed the heaviest direct mail effort since a gross reciepts tax was proposed unsuccessfully on business in 1975, the Council's finance and revenue committee voted 3-2 last month to reject Clarke's plan. In an Oct. 21 letter announcing the defeat, Washington told trade board members that their "letters, telegrams and telephone calls have, evidently, had an impact" and urged the business owners to keep up the good work.

"You should follow up with Council members Barry, Dixon and Shackleton by sending them a brief note thanking them for their vote against the bill," Washington wrote. He later warned, "The issue of classified property taxes is not dead. It will certainly come up again. The Council committee on Finance and Revenue is still considering ways to hold residential property taxes down."

Washington refuses to publicly discuss his role in the matter.