I've never been much of an HRC fan, but it's hard to see what she could have done differently, based on the information available. Aside from "don't be Hillary Clinton, with all the baggage that involves", of course. A candidate less well-known to the public might have done better in a "change"-focused election.
But she pretty much ran a campaign according to all the best practices, and lost to a guy who basically did everything wrong (within the scope of the campaign) that you could do wrong. The problem wasn't in the Clinton campaign. The problem was that the electorate didn't want what she was selling, despite a very good sales pitch.
I suspect there's going to be a lot of analysis focusing on exactly what level of positional compromise would have gotten the Democrats enough votes in the Midwest and Appalachian states to win (off the top of my head: an about-face on gun control and some sort of mea culpa on NAFTA might do it), but I don't think the Democrats could have known that in advance. Any more than any of the Republicans who lost to Trump in the primaries could have known how badly they were underestimating the latent anger of voters when they ran their own by-the-book campaigns.
I was really impressed with her performance in the debates. She must have unbelievable self-control. Her baggage isn't even her own baggage; people have been attacking and hating her for decades, apparently only for having the gall to be an ambitious woman in politics, while being married to a successful man in politics.
She looked smarter in debates, but came off very smug to me.
A little naive to assert people don't have real reasons not to like her. There are many. Tons of crap that in the Wikileaks emails that are not as damning as they asserted but do paint a clear picture of how dirty her campaign played. The Clinton foundation stuff. 1 mil from Qatar? Wtf
And for those of us who are anti war she has some responsibility for a lot bloodshed.
This is only a sample of concrete things that are definitely "her baggage".
None of that is unique to Clinton. Look at Trump's self-enrichment through his "charitable" foundation. Look at his extremely dirty business practices. Look at the many, many corrupt politicians in the US. Yes only Clinton gets this level of shit for it.
I'm not saying any of this is okay, just that many politicians, including Trump, are just as bad or far worse, but only Clinton gets this level of shit for it.
And her attacks didn't start with any of this. It started when she was first lady of Arkansas who wasn't just a conservative housewife but very politically active on her own. And then again when she was first lady of the US. That's what got the attacks started: a woman who didn't know her place.
Whose baggage is that? Because these exact things are also true for Trump[0]. He just didn't get as much attention for it, because everybody loves to attack Clinton.
[0] Maybe not the war with Russia, but that's also not true for Clinton, and Trump seems very eager to kill a lot of people.