Panel Line Colors?

Just finishing up my 1/72 Ki-55 Trainer painted trainer orange and i was using a technical pen with black ink to detail the panel lines. I did the under surface first, but it seems to me that black is to severe for this color paint job. Does any one have any suggested colors for panel lines for different background colors?
i.e. dark paint job- black panel lines, black paint job - grey panel lines.

Thanks

Burnt Umber is a good one. Any darker brown, and much lighter tones for areas with white paint or bare metal.

You may want to try using greys instead of black. For a light to medium grey aircraft, a dark grey wash works well. For a white aircraft, a light to medium grey wash would do well. For a dark grey aircraft (or black), a light to medium grey wash would do.

Or, you may want to darken the base color of your aircraft with some black, until you get a shade that looks like the color in a shadow. You can also lighten the base color with white for “highlilghted” areas. Pixilater has some great weathering techniques.