If I understand the geometry images paper correctly, you don't have to ship the original assets. The technique uses fancy topology to encode a mesh as an image

If I understand the geometry images paper correctly, you don't have to ship the original assets. The technique uses fancy topology to encode a mesh as an image --- x, y, z of each vertex being the r, g, and b channels of the image --- and pages the images into the GPU on demand. You can downsample the images as much as you want