Victorian houses used to hang pictures by supporting them from the crown molding. This eliminated damaging the expensive and often custom made wall coverings.

In your LQ you could do the same thing. If you wanted to hang a picture under a cabinet, a small quarter round molding fastened to the cabinet's bottom could support a string/wire going to your pictures. The wall  molding would work where there are no cabinets.

I have seen 3m fasteners advertised that adhere to walls and are removable. Whether they would adhere to leather and if they would not mark the material is an unknown.

Gard