I actually have spent about 2 years off and on working on a star chart of the known Haloverse. It contains all known canonical stars/ colonies, plus hundreds of others meticulously mapped onto a flat surface using actual astronomical data from various real-world sources. I even figured out the sector and sub-sector designations that define UNSC space. I made it internally logical and also had it fit all known instances of Halo designating sectors. The only one that cannot fit is Eridanus II cannot be in Sector 4. Everything else so far fits.

It's not complete yet enough to reveal. I kind of want to reveal it first to 343i because they could really use some astronomy knowledge from what I've discovered in making this chart. I had a teaser up a while back. I'll link it here but it looks much different/improved since then. (Yeah, it's much different now...I changed most of the color coding for the factions...)