Content Warning
While I love making my own settings for #ttrpg campaigns, I find the Procyon Sector from the #ScumAndVillainy rulebook quite impressive.
It's only 47 pages in a giant font (I'd say 10-12 pages in a D&D book). It has 12 planets, that come to one paragraph worth of description each. And 36 factions! That each get three or four sentences of description each.
And somehow this works! I feel I understand this world and its complex power dynamics, and could run a great game with just this.