I worry that she'll be a spoiler for anyone running to her left in the primary and more or less guarantee Biden is the nominee. I wouldn't hate her being president, I don't think the next Democratic administration will be able to accomplish anything Warren wouldn't be on board for regardless, but since she hasn't done much since Occupy was a thing other than make herself the brunt of Pocahontas jokes there are other just-barely-actually-on-the-left Democrats with better chances of winning.
My theory? She's running for VP. The next Democratic candidate is going to be a white male. The DNC is going to go centrist AF with the excuse that Ocasio-Cortez and the like are crazy Tea Party leftists and "CENTRISM" is what America really wants. Which means the inevitably milquetoast whitebread establishment white male is going to want someone to excite the rabble-rousing millennials. Which means a woman, preferably a minority, preferably a firebrand. Warren is running for VP against Ocasio-Cortez and Kamala Harris. She's trying to earn plenty early on so she can force concessions from whoever ends up with the nomination.
If the Dem's want to win they put forth the most boring White male candidate they can find. The Democratic heir apparent usually loses their presidential bid, Hillary, Gore, and Kerry. A dark horse governor often does really well for the Dem's, see Clinton or Carter. Obama was a dark horse candidate, not a governor but he won and wasn't the parties torch bearer. A bland white guy who is centrist, business friendly while being decent on generally leftist social issues will be harder for Trump to bait, lambaste and lampoon. A friendly guy who can give a sardonic smile and chuckle at Trumps bullshit while talking about non or less partisan issues that we should have been working on the past four years would starve the Trump campaign for that which feeds his base. Trump would be left with nothing but vilifying Nancy and Chuck. Warren has already shown her self all too eager to give Trump ammo in response to his side show, she would have done better to starve him with noble silence or aloof contempt. If John Hickenlooper could get some traction I think he'd kick Trumps ass. I could be wrong but he's got all the bonifides of a centrist governor who's boring as can be while seeming like a well balanced and pleasant dude.
Jay Inslee - governor of Washington State - is being touted as a potential Democratic candidate for the Presidency. Him as a successful Governor of a progressive state with a strong Republican minority... Warren as the die-hard representative of the DC Democratic machine... could be an interesting duo.