If you consider moving out from low poly art style, it would be pretty cool to have pbr materials with vertex painting channels packed with other shaders. For example a basic wall with the red channel with some grunge, the green channel with some broken plaster, the blue channel with some leakings, for metals like some rust, dust and paint splatters and so on, you get the idea. I think this could come quite handy for a lot of people when using materials and wants to break the tiling.