I am torn as to whether or not Bernie would have been better.
On one hand, he has a solid record of good foreign policy and being pro worker (though he has shifted towards being pro unrestricted immigration in recent years). And he is passionate about what he believes in + inspires a lot of young people.
BUT he is the face of the hard left in the US, and he would not have been able to disown the accusations of being very left wing that he tried with Biden.
He also has a tendency to tacitly or explicitly praise communists/communism which can be bad in places like Florida.
And I remember in the debate with Hillary, he got angry and turned red (while Biden looked cool the whole time).
Then there's Warren who I think would be the best of the three. But she is a old and a woman (which hurt Hillary) and Trump would keep calling her Pocahontas.
But maybe right wing media would be fairer to her due to Tucker Carlson's love for left wing economics (he even praised Elizabeth Warren and her book).