If there aren't any limitations for loading, it does not really matter so much if the vessel will have Sag or Hog till the time stresses are below limits.

Off course it is always better to have minimum stresses on ship. So keeping this in mind, we should spread the load so that we neither have Hog nor Sag.

If vessel is fully loading upto the loadline marks, then it is preffered to have Hog as vessel will then have some draft in hand and less chances of overloading or exceeding the loadline marks