My comment about adding color to the bare metal template was only because of the opposite-corners black and white overlay on every square of panel lines, if you see what I mean. I noticed them on your bare metal template and here they are also on the painted one.
This effect is not meant for all situations. it is specific to bare metal. Bare metal acts as a mirror and reflects not only the sky but due to the curved nature it can show other shades as well. This doesn't have to be mirror-polish metal, but even dull and worn metal has a bit of a sheen to it. It can and does even reflect the ground based on the curve of the metal sheets. In fact, it often shows a large range of shades and colors. The problem is this reflection is dynamic. AH doesn't do this kind of reflection mapping. Instead we "bake it on" in 3D animation terms, and that means we fake the result with 2D bitmapping. This is why you add that black and white opposite-corners effect. It makes the viewer think the surface is reflecting more of the world around it.
However...
This is only true of the bare metal mirror-like reaction to the world around it. For painted materials you will not find such an effect and it is out of place. By adding light and shadow to painted surfaces now you have changed it to make it look like they are bulging out at every panel line like balloons. This has an undesirable effect on the finished product. It's fine to keep it for a BMF P-40 down the road, but I think you need to ditch it (the effect) for this skin.
EDIT: Keep in mind there are other effects you can use with painted surfaces. Different effects show wear, show sand blasting, show sun baking, etc. You have to tailor the effects to the aircraft you are re-creating. You need to have an eye for the historic condition of the aircraft itself.
