yes, loopcuts can help to reduce the dark shadings.the reason for this is,that if you have a quad polygon at the edge,the normal from the surface gets averaged.if you put a loopcut at the edge,your quad keeps the normal direction,and the small face at the loop/ edge becomes the average.hm hard to explane.
you can try this addon,it helps to calculate the normals for you.i would do the loopcuts before.
about the mats.you can asign in edit mode the selected faces,you want a material.or you can split your handle,and blade ect to separate objects.