I might use this for my Andromeda Sector, I would roll a 1d8 for the z-axis for each of these star systems. My sector 11 (K) is a bit sparse, in 3d maps there is more space, I want to make most of these reachable by Jump-2 starships. I might also want to combine some star systems into binaries and trinaries. In my system of World generation each component of a binary or trinary gets a mainworld if they have seperate habitable zones, that is if they are close and have only one shared habitable zone, then it gets only one mainworld, otherwise it gets one for each.