Version 2 with procedural spots. Procedural as in you don't need to mask them in manually.
Could probably be mixed with another iteration of the spots shader with another seed and scale, but just wanted to come back to this and fix it from the original idea. And nice thing about the spots being a shader based on voronoi, is you can use the spots shaders colour for masking colour adjustments or even "sinking" the holes with displacement.