They let him off the hook. Why bother investigating the rest, they are just wasting more of our money...
Excuse me, but not only is Comey not off the hook, their findings were enough to book him with lawsuits by individuals for the remainder of his life. He goofed. He intentionally did things to secure his job, and they were wrongful actions that almost killed the voting system we have in place by order of granting states their wishes for entering the union. It is called a sacred trust. His actions also discouraged law-and-order men and women whose high standards would never allow them to go against their good judgment to the point of being canned for being "troublemakers."
Comey was likely the poster boy for how to keep your job when your boss the president requires preserving criminally corrupt face-saving and that elected president or person running for office was wrongfully shown to be an upright man or woman when the reverse was true.
Since the FBI is a paramilitary group, I am not surprised the IG and the AG let him off for obeying a direct order of the POTUS or former First Lady whose welfares are both protected by laws or traditions.
I'm afraid we have fallen into the same trap as the Europeans have for Royals, or even worse since they are elected from the millions of people who do not know them personally and depend upon the press to give an ear to both their good and their bad points.
The only way we can fight it is to ensure that the future presidents of this country have served the military and been discharged honorably following a minimum of 5 years service in a military leader's capacity.
This case begs for finger printing and eye scanning to validate the person at the polls, and eliminate all online voting. If a person is too sick to show up to vote on election day, he should pass the baton to the able-bodied citizens to choose their fate.
And that's exactly what I think. All else is like Master and Commander's joke about the two weevils, and that the least bad one was the lesser of two weevils.