It is impossible to approach this topic from a truly neutral viewpoint. It is obvious that something bad happened in Benghazi and steps should be taken to minimize future occurrences.
My prejudice is that Republicans have a very long history of distortion. They have demonstrated they don't believe in compromise as they are "principled." They don't accept that they lost the election and in fact the biggest leverage they have comes from gerrymandering and abuse of Senate rules. The majority of those who actually voted (and Republicans have done their best to limit the number who could vote) voted against Republican policies.
Having said that, the Democrats have to accept that they had the responsibility when something went wrong. It is also true that at the time the Democrats were positioning themselves as protectors in a terrorist infected world in an election that seemed up for grabs. It was in their interest to downplay the threat and any mistakes they have made while the Republicans were organizing efforts to stir up emotions.
The points I have heard raised by Republicans are superseded by a few basic facts. The CIA was heavily involved and for security reasons (and perhaps to protect their own interests) wanted to minimize public awareness, particularly enemy awareness of details. The critical decisions that were made were decided by military. A key problem was that security expenses had been pushed down by the Republicans.
Susan Rice who in my opinion has done an excellent job was attacked for reading talking points that had been agreed to by the CIA. Republicans so anxious to find some dirt didn't hesitate to expose names of vulnerable people, thus scaring away potential collaborators. Reminds me of the Valerie Plame outing which some might consider treasonous.
There will always be problems. The Republicans suffered a lot of embassy attacks with more deaths than Benghazi and were always self-righteous regarding "Islamic terrorists" nevertheless thought that security budgets for embassies should be cut.
More recently I think they have a better case about the IRS investigating conservative groups for tax exempt status. I think all groups should be investigated for tax exempt status, but on a fair and random basis.
Do I think all Democrats are saints? No, I have been disillusioned that they are influenced by big money almost as much as Republicans. Republicans do not have policies that benefit the bulk of Americans and know it and find it more effective to find scandals. Perhaps the media is really liberal, but it does seem that it is not pure in all this--they love controversy for their ratings and they are tied into the economic establishment and are far less independent then they once were.
The Republicans tried very hard with Bill Clinton and finally reached impeachment proceedings that really had nothing to do with high crimes or treason. The Republicans really did enter a war in Iraq using false premises (hard to believe that they were not aware of their own distortions). They let in colleagues who made a lot of money from that war. They lowered taxes and all sorts of regulations and are very proud of that. They dislike being restricted in any way regardless of public benefit. The result has been an increase in inequality that is counter productive to the majority of Americans.
Hilary Clinton seems to be the target, but in reality she has done a very good job and is so popular that many assume she will run and easily win the next presidential race. The Republicans are making claims she tried to cover up, but really that is a stretch. Republicans have no guilty feelings about the Iraq War or the financial problems of United States, but are always looking to fault others. If Americans would like to earn the respect of the rest of the world they have to stop falling for self serving accusations of politicians and concentrate on the policies and the real problems facing the world.