This is something I had just thought of but on the nacelle struts where it has the grooved sections just forward of the "E" sections, would it be feasible for builders to paint those sections something dark like Metalizer Gun Metal. Color the section there around the grooves masked off from the rest of the strut. Seal the metalizer with the sealer, apply a clear gloss coat like you did in this build, and then use something like a silver or aluminum acrylic paint as a sludge wash to lighten the areas in the grooves, and wipe away the raised areas leaving the dark lines. It was just a thought, not sure if it would work or not. I'm a much better graphic designer than model builder so I'm not sure about it, but I know you can use lighter colors in some aircraft for panel lines on darker paint schemes instead of a dark wash and get a good worn effect.