I am considering what to do for adding roads/paths into the game, and am thinking that instead of making them as regular .vpp models like everything else, you could really just specify a color and the game could color the terrain in the color of the path. Of course, it could be a color with "noise" like most of the ground is now, or also a speckled combination of various colors (sort of like the current slope tiles):
But I am thinking that from a performance perspective, basic roads could probably just as well be painted straight onto the terrain instead of having to load a bunch of models into memory.
Really it wouldn't just have to be random noise either, it could be a pattern like brick or tile and you could specify which colors to use, or it could even be a .png image.