Easy. She's a smart able and policy focused person with a record of achievement. She's about the job, not the show. Of course she's flawed, but we all are, but the rest of us don't have a 40 year public record, there were problematic decisions but not once has evidence been found of willful wrong-doing.
I don't see anything very impressive about her resume. A botched health care reform, very uneventful Senate term and I'm not particularly wild about her time as SoS ("Reset", mishandled Libya and Syria). Obama's second term was much more successfull in foreign affairs.
I agree she had a lot of experience, but let's drop with this "muh great accomplishments" nonsense. It's also irrelevant. Many successfull Presidents had poor record before. I mean, what was Obama's resume?
In my opinion (biased, like every personal opinion) Hillary seems like a very generic politician. Of course I take her not just over Trump, but basically any Republican.
As far as personality is concerned, I actually find her much more likeable than it's being frequently suggested. Certainly better than Bill.