The population of the GA is probably the most diverse in the galaxy, with representatives of every race group controlling one planet or another. Still, the majority of systems are held by Human or Mythic races, as they were the first to develop BioWarp drives and colonize uninhabited planets(Or, in some cases, take over inhabited ones).
The Golden Alliance is in control of the galaxy's political machine, and their style of Representational Democracy is the standard that most planets follow. They also head galactic council meetings, and all the other known factions save the Watchers are expected to attend once per year. These meetings are also representational, with diplomats or senators from each group of star systems arriving to decide on what's best for the entire galaxy. Needless to say, these meetings are extremely confusing, last weeks, and not much is accomplished in the end.
Golden Alliance military forces follow a variation on a common naval command structure, divided into Enlisted ranks, Officer ranks, and Warrant officers. BioWarp Mages, who pilot specialized starfighters, certain weapon systems, and the warp drives in most ships, are considered High-level warrant officers, and their orders usually override all but their ship's commander's. Troop transports, freighters, and frigates are usually under the command of a single captain or major. Battleships are usually led by a Colonel or Vice Admiral, and the largest ships--space stations and carriers--are used as the flagships of a fleet and are commanded by an Admiral. There are a dozen fleets of ships within a division of the GA's space force, each fleet given a zodiac name. The divisions themselves are named after the spiral arms of the Milky Way, and ships and the crew aboard them refer to themselves as being in the fleet of the division, E.G. "Gemini fleet, Cygnus Division". There are about half a dozen divisions in their space fleet.