Additionally, zero of those 3 emails actually contained classified information.
You realize that that doesn't actually matter, right? The contents of the information is irrelevant, it could be a weather report for all the government cares. The fact that the documents were classified is what makes mishandling them a problem. The issue at hand is that it is not up to Mrs Clinton what is and is not classified, or how to handle that information. Personally, I don't even care about the criminal prosecution. This whole situation underlines a flaw in her character that IMO makes her unfit to lead a country.