Even when Jack was a conman trying to con the Time Agency in order to find a way to retrieve the missing two years of memories - he wasn't strictly a bad person. From all that we've witness and had told to us, he never deliberately tried to hurt innocents and honestly proved his worthiness of respect and care when he voluntarily offered his own life in an attempt to stop the bomb from hitting the Chula Ambulance in London 1941. And as is often remarked, he had no indication from the Doctor that he could be saved by the TARDIS and the Doctor. He then truly sacrificed himself for the Doctor on the gamestation but all that Doctor did was save Rose and then sacrifice himself for Rose and ignore and runaway from Jack. When placed side by side - I think history would judge Jack the better man, the better being in the short and long term.