Just some thoughts.
Vice-President: Senator
Jim Webb (D-VA).
Secretary of State: Governor
Bill Richardson (D-NM).
Attorney General: Former Senator
John Edwards.
Secretary of Defense: General
Wesley Clark (Ret.).
Secretary of Labor: Mayor
Antonio Villaraigosa (D-Los Angeles)
Secretary of Health and Human Services: Senator
Hillary Rodham Clinton (D-NY).
Secretary of Veterans Affairs:
Paul Rieckhoff, Executive Director and Founder, Iraq and Afghanistan Veterans of America.
UN Ambassador: Congressman
Dennis Kucinich (D-OH).
Secretary of Homeland Security: None. Abolish the office and department as a failed remnant of the Bush era. If it can't be abolished:
Richard A. Clarke.
EPA Administrator: Senator
Barbara Boxer (D-CA).
Consumer Product Safety Commission:
Ralph Nader, founder, Public Citizen.
There are of course many other appointed positions (cabinet and otherwise) on which I don't have a clear pick. Treasury, Interior, Agriculture, Commerce, Housing and Urban Development, Transportation, Energy, Education, World Bank, FBI, CIA, NSA, FEMA, NASA, NOAA, FCC, OMB, DNI, Science Advisor, Federal Reserve and I'm sure more I can't think of right now. It would be good to get some of the few Democrats who tried to take a stand during the last several years into the Obama administration, but on the other hand we don't want to deplete the Dems in Congress and risk another GOP takeover.