4.50m Sailing Yacht Concept

GZ curve values can not change with the position of passengers. If there have been changes it is because the current model is different, includes the house, from the previous one.
As I said earlier, without calculating the lightship weight and center of gravity position, not worth taking additional measures or correct anything. You're flying blind.
I think you may have noticed that you need, inevitably, do many calculations, by hand or by some software.

 

It is fairly common to do radiused chines in strip planked cedar or similar lumber with everything else in plywood. You would want to glass the inside of the strip planked chine, the outside would get glassed when you sheath the plywood. Another way if the radius is not too large is the way the searunner tris were done. Rather than having a chine log as in typical plywood construction they had a stringer set back from the corner, let the plywood run by until they met, heavily glassed the gutter between the stringers and then rounded over the outside, then sheathed the whole thing.