The wash sounds OK, but for the hinge lines of the control surfaces, try using a pencil. The retractable type are good for this, having a fine 'lead', which can be sharpened to a chisel point on a piece of fine grit wet 'n dry or sandpaper.
Do one pass with the pencil at first, and if you then think it needs more highlighting, do a second pass. Blow off any graphite dust that may be left in the groove, and any 'silvery' shine from the graphite will disappear under a clear matt coat.