My first two hurdles are the map and the colours. The map needs to be a fixed size and can easily be copy/paste edited with world edit https://github.com/Uberi/Minetest-WorldEdit/blob/master/Tutorial.md but I can't seem to get a map to not generate and I need the map to be dimly lit so no daylight, which then poses the problem of seeing the editing.
As for the colours, I have a clear idea of what to do about colours and textures. A base of 16 colours is needed, 8 primary colours and 8 shades, as specified here: https://github.com/chriskempson/base16 from there we need a script that can do hex math. Halve each hex value and add them together in sequence, that's 16x16 colours creating a full 256 colour pallet which we can import to gimp. From there we take real world images, resize them to 128px texture size in gimp, and use colour indexing with dithering to convert the textures to our colour scheme. I think tomorrow-classic-dark is good enough, I tried more poppy colours for a real neon cyber feel but on large scale it made it look like a fiesta/too cartooney, but that also wasn't using a full 256 colour range but I think toning it down is the way to go. I have yet to figure out a python script to create a list of hex values, so doing that is my number one priority now.
These are the 16 colours I was thinking of starting with, pic related. #151515 #202020 #303030 #505050 #B0B0B0 #D0D0D0 #E0E0E0 #F5F5F5 #AC4142 #D28445 #F4BF75 #90A959