Weight - integration in items properties / layers

[Jybel]

My layers are usually organized by material, e.g.:
rhino layer name
- hull   alu 12mm
- hull   alu 10mm
- deck alu 10mm
- deck alu 10mm
- deck alu L 50x50x5mm
- deck alu O 150x30mm

I'd like to assign an orca material library to rhino layers:
rhino layer name               orca material
- hull   alu 12mm               surface alu 12mm 2700kg/m3
- hull   alu 10mm               surface alu 10mm 2700kg/m3
- deck alu 10mm               surface alu 10mm 2700kg/m3
- deck alu 08mm               surface alu 08mm 2700kg/m3
- deck alu L 50x50x5mm     solid alu 2700kg/m3
- deck alu O 150x30mm      solid alu 2700kg/m3

and keep the option to assign to an object a different orca material than the object layer orca material