This could possibly be done through an add-on or become a built-in feature in Blender. Next to using weight-paint information you could add a low-res texture with color information (each channel meaning something different) to specify the pore-density, size and maybe stretching should be placed.
If you do this for specific kinds of skin features separately one could save a lot of time and memory to make a highly photorealistic model. All that would remain to be sculpted would probably be the wrinkles, scarring and other imperfections