Obama is about as bad as bad can get. He has to go.
It needs to be a VP who can step in and one who can follow on in the next election for pres.. And someone who doesn’t distract from the nominee... Sarah hasn’t even endorsed the nominee, so that’s a no-brainer that she wouldn’t be asked - probably would accept anyway, she’s on a different career path.
It’s a tough decision. I don’t know anyone who fits it right now.