Ha! You're cutting right to the heart of things by asking what it's for, aren't you?

The Cathedral Galaxy is a personal project of mine. I have written a few short stories that take place here, and I do have an overarching plot in mind. I don't have a particular purpose in mind for this map series other than to build out details of the setting, practice my Photoshop technique, draw cool space megastructures, and give the setting a unique series of illustrations/maps. There's not a specific gameplay environment in mind, though I am aware of one RPG group that's been using it for their adventures. (Man, would I love to play a Skyrim-type PC RPG in this galaxy! But that's a pipe dream.)

For the two options above, I was really just thinking about aesthetics and "terrain" variation within a map. My raw material mostly shows stars as dots, and I was looking for a way to add interest (and indicate that there are more settled worlds than just the homeworlds, besides). But there's not really a specific purpose in mind here -- part of why I'm on the fence about adding so much stuff to the map. Also, yes, while each regional map had a unique highlight feature (like the trade resources in the Traders' Rim) I was thinking of adding inhabited worlds to all the regional maps.