I've developed a crude method to easily make SE4 pseudo-3d race styles based in SE3 shipets.
Using a displace filter in 3d studio to give height acording to brigtness, and the same pic as texture map.
Example using one of original SE3 races
Results look surprisinlgy good considering ther are based in icon sized 32x32 pics.
Using better source images (and multiple images if necessary) results can get be really better.