I think choosing Warren would be a terrible mistake and I’m not someone who wants to give Hillary good advice. An all-female ticket would be disastrous for the Dems as it would drive away the male vote in a bigger way than usual. Plus, Warren is a radical liberal - and not particularly intelligent from what I’ve seen of her.
That and it would be 2 E coast liberals. I doubt the western US would look highly on it.
All the more reason she's an excellent choice. We should be so lucky she'll choose her, but afraid she's not that dumb