I know that this isn't part of the current doc, but I'd like to take the liberty of presenting some conceptual ideas about an element that has been quite problematic to traveller: star systems.
Science advances. Those new torch orbit gas giants are weird, unexpected, and hard to model. Stellar type is always a contentuous issue in the details. Solar system dynamics are only somewhat known in depth in one case (us). Finally, given that our most up to date extrasolar system data is , by definition, based on extreme outliers, any attempt at modeling is doomed to obsolescence.
That said, I suggest that the problem lies in what the sector maps are intended for. Conceptually, a better approach to the problem is to view them as charts rather than maps. The difference is that a map is detail and accuracy oriented, and highly descriptive. A chart is only accuracy oriented when it is functional. A great example is the age of exploration portolan charts - they have very fiddly detail about coasts, the depths and hazards within a few miles of the coast, and where fresh water is available on the coast.....and nothing else, just white space, inland. They were for Navigators, not cartographers or scientists.
I think reframing the traveller system maps this way will help. The subsectors are already obvious functional abstractions, given the actual stellar density compared to the charted planets with starports. They are clearly a navigators reference: where are the ports the inhabited planets, the interesting stuff; and where are the shoals: red zones, and rifts.
From the viewpoint of a working navigator, It seems like you need a bare minimum of information other than the planet.
1. where is it (which orbit)
2. Are there other important ports insystem.
3. how big is the 100/10d limit for the star
(this actually should be priority 1, I imagine,)
4. since we may or may not be playing space opera, and optional consideration is where are the asteroid belts .
5. where are the gas giant(s), if any.
A trader may have one more question: are there useful resources off(main) planet.
So, the question is, I feel, NOT how can the generation system model real astrophysics, but rather quickly allow a GM to answer the above 5 questions.
So, for my campaign, the info is generated by
first rolling the jump shadow(JS) of the star: 1d6 orbits. Assumption: a BIG star has BIG orbits, so it scales.
second, rolling the number of significant orbits : 1d6+JS
Locally, significant = out to Neptune, say.
third, any gas giants ? 5+ 2d6 = yes. # =1d6 -1d6 + JS
fourth determine Habitable zone. Roll 2d6. The low dice is the number of the first habitable band; the high dice is the orbit number of the first orbit outside the habitable zone. tie means no hab zone .
The orbit defined by the high dice (or the tie) is also the last of the inner orbits. (see next item)
fifth, roll 2d6 for each orbit.
Boxcars indicates a significant (close) companion star;
Pairs suggest a gas giant, if any exist (from above)
in the inner system, only paired ones (snakeyes) places a GG; in the outer system any pair, or a total > half the orbit . (stop this step once you've allocated all the GG)
Then, use one of the individual dice to identify the non GG occupant of the orbit.
For inner orbits, look at the lower dice,
for outer, read the high one :
1= empty , 2=small rock, 3= large rock, 4= planetoid or belt 4= small ice, 5= large ice, 6 =planetoid or belt.
For orbits with GG , one can either read the high/low dice as above, placing it as a moon, or just ignore it.
Final step: the planet. The main planet goes in the hab zone if earthy, the closest other inner zone if hot, the closest outer zone if cold. If there is a GG in one of the orbits suggested, the planet is a moon. Vac worlds can go anywhere. Asteroids/planetoids are in the belt or planetoid orbit closest to the hab zone or last inner system orbit, or can be a moon of a planet in the appropriate orbit.
One can also use a GG to place an earthy type world in a system with no hab zone, a vac world, or an asteroid world in a beltless system: make it a moon of the first GG outside the hot zone; promote the GG to BIG GG. Otherwise, place it in the last inner orbit and improvise.
A stellar companion is always in the last orbit.
Done, all with d6, no more than 2d dice per fact. Note the use of the hedgeword "significant". There may be more planets, more moons, a farther companion, a system around the companion, etc. They just aren't interesting.
Cap.