Some ideas for the governments:
A highly bureaucratic government that is centered heavily on its homeworld, with all its "colonial territories" producing resources just for that homeworld. Think Trantor and the Galactic Empire from The Foundation. Internal strife is extremely high, barring other factors.
A Federalist empire where power is spread equally among all the planets, and no one planet has more power than the other. There is no "central" homeworld, as with Earth for the Federation or Aurora for the Aurorans in EVN, and as a side effect they rely heavily on trade to get what they want. (This also means there's no world where you can get all the outfits from the entire empire; you have to travel to get what you want.) Each planet has a representative, and they assembly at one of the planets on a regular basis. Depending on the nature of the representatives, the government could range from corrupt and slow reacting, to hamstrung by argument among planets, or to angelic and near-problemless due to the spotlessness of the representatives.
A warrior society where military tradition is ingrained into every aspect of a citizens' lifestyle. Everybody who can pilot a fighter, captain a battleship or shoot a rifle does, and will, fight. Their level of organization is nearly flawless, and they know better than to fight among themselves. Think about Rome on a galactic scale. Not to be confused with Aurora; they might tattoo themselves, for example, but to do so only shows their rank and/or affiliation with the military. They're relatively clean shaven and well dressed, but they have decades or even centuries of military experience under their belts, so watch out.
A small, scientifically based government who has brilliant leaders and whose every action is to advance science in any way possible. The technology they develop is used to make weapons, outfits, ships, you name it, and can show up in virtually every aspect of their society. They may not be the Jetsons, but they're pretty close. Their past is what forced them to become so ingenuous, whatever it was, and they use their technology as a bargaining device to keep other civilization from taking them over. Think the psycho historians from The Foundation.
A loose confederation of planets that argue among themselves and can never agree on anything, except on when it's time to band together and confront an invader. They cover a lot of space, and could even be "geographically" isolated from other parts of the confederation. This would make wars between this government and others interesting, since they make tempting targets when they are separate, but are a brutal force to be reckoned with when the ball's up.
Just a few things to get you started. I'll post that all into the drop box here in a second...
This post has been edited by JacaByte : 20 October 2008 - 10:37 PM