Ahem, I am a member of this board for a mere nanosecond, but I hope I can provide some input as the things you are discussing are directly connected to what I do OOC. Namely, I am a game-theorist working in field of political economy(a social scientist) who directly investigates how democracies become dictatorships and vice versa. I've read all four pages of your thoughts and feelings and I must say - things you are discussing are really far from trivial.
Esentially, since this is the Galactic Republic, I think we all agree on the fact that it has to be a democratic society, where politicians wield real, but limited power. Designing a mechanism to keep GR a democracy rather than an oligarchy or slipping towards dictatorship is going to be hard. Politicians have allegiance only to their ego, with very few exceptions. I am not saying I have some magical solution which postulates how people should RP their characters, but it would be of essence to consider the following when performing a dominion - have dominions which are purely political influence, like joining the European Union. There is no revolution, no war, just a "friendly" takeover. Don't know if you had these in the past...