Do I understand it right that excluding the two metal layers, there's only a single "layer" of "logic" inside? I reckon newer CPUs have multiple, making imaging based reversing more difficult?
Even modern chips have a single layer of transistors, although there is research into 3D transistor stacking. (Flash memory stacks dies for more density.) Modern CPUs have much, much smaller transistors as well as constructing them more vertically (FinFET) but it is still a single layer. Modern processors can have over a dozen layers of metal, while the Pentium I examined has just 3 metal layers. I'm not going to be reverse-engineering a modern chip since you need an electron microscope to see the features; the features are orders of magnitude smaller than the wavelength of light.