None of the CBs are what we need but they aren't the reason we keep losing games. Total lack of ability to keep the ball or threaten in the final third need addressing first.
Unfortunately we have very few (if any) players with both passion and genuine ability. When the chips are down this becomes a problem, not to mention the awful lack of leadership on and off the field.
Hazard strikes a ball better, has more pace and far more vision/intelligence. To put it down to a few extra fitness sessions and a bit more mental application is ridiculous, even by your standards.
Great players like Hazard have no discernible weaknesses and if they do, they work on them and turn them into strengths. I love watching Hatem but you can't compare his ability to Hazard's. Different leagues.