I believe Mrs.BHO would be the best choice for running mate.
Most qualified centrist Afro-American female. She would galvanize the minority voters. Based on BHO she would not follow elitist liberal lost causes as per deplorable HRC. She claims to be not interested, but can she walk away?
Do not mistake "I am a good first lady" for "my politics are the same as my husband's," Luee, regardless of what you think of HRC.
And it's a hoot hearing you describe Hillary Clinton as following "elitist liberal lost causes" given that one of the reasons she lost was that she was seen as a corporatist moderate by the "elitist liberal lost causes" advocates.
I also think that only one of the women being discussed is a threat to your precious avoidance of liberality and that is Elizabeth Warren. She is not only far to Biden's left, she already has his respect and his ear in ways Bernie never could. You should be grateful she isn't Black.