The Assembly is composed of 63 Speakers, one per world. Every six months, one of their number is appointed Prime Mediator, who enforces the rules of procedure and does not vote except to break ties. Different areas of government, such as Tarrifs, Economy, Regulations, and Minimum standards of Education and Health throughout member worlds and headed by Ministers.
The Legal System is adjudicated by 63 Legates, one per world. All Legates are experts in the laws of all member planets and of the Assembly.
The Fleet is headed by The Admiral. There is only one at a time, and the rank expires when the job does. Retired Admirals are addressed as Commodore, a purely ceremonial title.
Fleet Captains oversee large groups and operations. Individual ships follow the Captain -> Lieutenant -> Ensign structure of most RL modern navies. Enlisted are either Warrant or Petty officers, or Chiefs, or some combination that makes no sense to anyone not in the Fleet, and many who are. The rank and file are referred to as Nautics, jokingly nicknamed Naughts by everyone including and especially themselves. There are also grades, someone may be a 2nd Lt., Jr. Ensign, or Chief Petty Warrant Officer 5th Class.
Patrol is below Fleet, but operates effectively separately. Think Fleet -> Patrol as Federal vs State/Provincial law enforcement. Patrol Offices are a lot like Lancers, but a lot less fun, a lot more organized, and much better funded. The prime difference is Patrol will not intervene in a local matter ever. (In the brief shooting war between the planets Cipactonal and Oxomo over control of an equidistant naked singularity, Fleet kept the hostilities from spilling out of declared combat zones, Patrol escorted non-combat traffic. Neither world dared oppose them.) Both Fleet and Patrol actually spend most of their time as de facto police, customs, rescue/first responder services and a great deal of community service and charity.
Patrol is controlled by the Marshall, similar to the Admiral (to whom they answer directly). Retired Marshalls are given the ceremonial rank Inspector, which has no active field equivalent. Patrol member ranks are Colonel, Commander, Major, Sergeant, and Agent. The rank Sergeant-Major exists for those in training or oversight roles that do not involved field work.
Any gaps need filling?