Yes, that was my thought too. There isn't really any reason to define north as such, for example. On the other hand are raw data values like "towards negative X" or something kinda abstract for human beings. I just hoped that someone had defined it, simply for completeness sake.

You actually can't define it as north, east, south, west because unlike a planet; each direction has an end. If you would stand at the edge of the world; you simply wouldn't have that direction anymore. Those directions would also only be sufficient for the angle, not even the position.

About the positioning system;
It seems like you start with the coordinates 512.0 512.0 527.0 when doing newmap 10. The Z-axis seems quite interesting, as when doing newmap 11, the coordinates of the X- and Y-axis are multiplied (1024.0 1024.0) while the Z-axis isn't (1039.0). It seems like the Z-axis has an offset of 15 units against the other axis.

I had plans to make my thirdperson script work with getcamyaw and getcampitch commands, but never got around to it. I was thinking if you moved your crosshair 10-20 ish pixels in a direction, the script would move the camera left/right or up/down.
I know it's possible, but imagining how it work, it would seem annoying, the camera would be constantly adjusting position thus making aiming harder.

Though a bind to switch sides could prove useful.

As for directions, you know that little red cube in the corner of a selected cube, aka the paste direction? I always assign that to south-west.

all the ents are higher than the 'ground'. so is the playerstart, so is the player itself. If not you'd be inside the ground.
Dunno if the +15 is the height of the ent or the height of the camera.

It's the height of the camera.