Many people have not needed to really examine her policy positions in detail. They aren't New Yorkers who needed to decide whether to vote for her as Senator, or a Democrat who needs to determine whether to vote for her in a primary/caucus. I know I don't spend a lot of time thinking about people who I can't even vote for. If unlike the last two elections she actually becomes the Dem nominee then people will start examining her policy positions in detail as a general election candidate.
That being said, even with that above disclaimer I can think of several things right off the bat that I disagree with. She's pledged not to raise taxes on those making less than $250k, if you're going to raise taxes then that income limit should be far lower, certainly not above $100k. The $250k limit is basically pandering to people in high-cost urban areas who should by no means be exempt from paying higher taxes to pay for the very stuff they're advocating.
A second would be her reflexive dismissal of any even tiny move towards de-federalizing retirement plans (e.g. "privatizing social security'). Even giving her (probably undeserved) credit that she's expressing her honest opinion that doing so is "saving us from ourselves" in case of stock market decline, etc. as a people we'd still be better off with assets that we have direct ownership over and aren't subject to the whims of Congress. I'd rather have a self-directed retirement account that went down 75% in a stock market crash than the zero I could get at any point because SS is entirely payable at the whims of Congress. And don't give me that "we'll vote them out" crap, that's not an acceptable answer. Either our own money that was taken out of our paychecks belongs to us or it doesn't, and right now it doesn't and is just another tax. SCOTUS even confirmed that fact:
https://en.wikipedia.org/wiki/Flemming_v._Nestor
A third would be her stupid and knee-jerk support for gun control policies. She wants to go back to the assault weapon and other bans despite the fact that (A) it should NEVER be a federal issue and (B) it doesn't fvcking work. It didn't even get renewed last go-around because the damn thing was so worthless. Everything about these types of positions tends to be completely arbitrary and idiotic, as if a black AR-15 variant in .223 was somehow a tactical nuke whereas the far more deadly Remington 700 is perfectly fine. Only morons could look at the picture below and think "we only need to ban the bottom gun because of how dangerous it is, but the top weapon is a hunting rifle."