You might be interested in this link - it has casualties broken down the sides, battles, and percentages.
Very interesting link! I agree with what you say about those who denegrate and dispise the bravery and sacrifice of our heroes of the past. I've never been a Civil War buff but (in my opinion) one of the best and most comprehensive histories is the 3 volume work by Shelby Foote. What's remarkable about this is that it's so readable and it captures the humanity of the struggle. To me, it takes a great writer to capture your attention, make history "real", and write in a style that's engaging -- but without oversimplifying a complex subject. Anyway, that's my two cent commentary!
Well, to the extent any of these men took oaths to protect and defend the United States of America, they were traitors to the USA and to their oaths. They may have found such treason to be justifiable, in the same way the Founding Fathers' treason against the British Crown was thought by them to be justified, but it was objectively treason. That being said, no one should spit on anyone's grave.