Nice that you are working with the idea of backgrounds tied to a common faction. I'll allow suggestions of the faction nuances, like the name of the prestigious Union-based school.
The idea of these factions is that the world is a collection of city states ruled by a world government. Over time, people distrust the suppression of truth and history by the Union, and wanted some competing new blood to become the next potential world government, and so comes in the United Advancement.
For centuries, the Union have access to rocket tech, but wants to keep it unused and as a secret. Seemingly "over paranoid" about the dangers of going back to space after the ancient alien war. It was the UA that broke through this limit, much to frustration of the Union due to their overall weakening power.
(I just enjoy respouting my lore.)