Tapani Alliance Senate
This is the main senate body of the Alliance of Worlds. Each member government from across the known galaxy is represented in the group. They are one-third of the structure of the Alliance of Worlds and are modeled after the senate from the old Galactic Republic. From the journals of VN Ysadora They meet on Estalle Island (usually) and decide the joint fates of several galactic nations. Also they argue a lot. Also they derail their own conversations a lot. You would think they get little actually done, but no: so far they are surprisingly effective on the matters that an individual government cannot really handle alone.
Emperor Gregor Vortapani is the President of the Senate, with the power to oversee debates and discussions and to appoint or instruct various Senatorial Committees. In practice, he mostly leaves that duty to the elected Vice-President of the Senate, who is chosen by majority vote of the attending Senators. Each member government contributes one Senator according to the rules of their government, usually but not always determined in some sort of local election. A "member government" is a government of one or more planets which has signed onto the Tapani Alliance Treaty (and is bound by its terms regarding sentient rights and so forth). By terms of the Tapani Alliance Treaty, each Tapani Sector Province elects one Senator. Some other governments regularly complain that this gives the Tapani Sector too much power. Count Shep Vorjion of House Melantha always responds by suggesting that the Senator doing the complaining could petition Emperor Gregor Vortapani for the opportunity to join the Tapani government. High Lady Varin Arabella, Countess Vorbarnaba, at least once shut down the complaints by pointing out that it was Tapani who put an end to Darth Sidious, at great personal cost, while the honorable Senator Whatsyourname was busy keeping his Imperial head down. Finally, the Alliance to Restore the Republic will continue to have one Special Senator, appointed by the executive branch of the Tapani Alliance -- specifically, by Chief of State Mon Mothma -- for the first thirty standard years. This lets the original Alliance outlast the duration of the Imperial Period.