@Schlemm
Yes, I understand what was Your idea. The method described by Acelanceloet is probably most common on SB nowadays. It uses basically just 2 shades - ">45 degrees" and "<45 degress" -but it's not able to effectively depict such hull shade as here.
But then You have "flat of side shade" and "not flat of side shade" plus a darker tone that's used in the area above propeller and on 1-pixel thick stripe along the keel. And at the same time You seem to overlook, that for example on the bulbous bow You'd have places that are facing up/front (so towards the source of light as understood by SB practice) so should be marked as highlighted.
IMHO with a hull shaped like this, it perhaps makes sense to have
slightly darker shade for "not flat of side" areas (or perhaps, maybe rather
slightly lighter for "flat of side"), but also to combine with "45 degree practice" (where 45+ deg. areas are marked with
much darker shade.
What I mean is a hull shading that would look more like this (mind it's just a VERY crude, simplistic drawing that is just meant to convey the general concept):
EDIT: to me it would also make sense to have that "flat/not flat" line clearly marked (the way panel lines are marked, for example), but the different shade reserved to areas that are at an angle exceeding certain value ("very much not flat") but less than "45+ degree", though it could be difficult.