Well, she's definitely further left than most Democrats. She has a record of being tough on Wall Street.
However, she's voted for increasing the military budget a few times lately (as have many other Democrats, unfortunately). So that was quite disappointing of her.
In some ways she also comes off as a bit opportunist. She chose not to endorse Bernie in 2016, likely because she didn't want to get on the bad side of the Hillary-wing of the party. She's a bit of a calculating politician - and she used to be much more honest, aggressive and opinionated. So it appears that being in Congress for a few years has changed her, and not in a good way.
Overall, I guess you could say she's somewhat Bernie-lite. But Bernie is certainly to the left of her. Personally, I would easily vote for Bernie (or even Ojeda or Tulsi Gabbard) over Liz Warren in the Democratic primaries. However, I would have no problem casting my vote for Warren in the general election. If the nominee is somebody like Joe Biden, I would just vote third party probably. But yeah - Warren meets the ''progressive enough'' threshold where I would vote for her in the general election.