The Wookiepedia says on one page that the Empire includes up to 1.5 million member worlds and 69 million colonies. At a 46 to 1 ratio, a grid square has about 4,300 member worlds out of the 200,000 total. But that's not consistent. Also, I did see other numbers quoted, and that the number of worlds may be in the thousands galaxy wide. One source says Lucas said 24,372 worlds. Going with the crazy high numbers and crunching some numbers, with a lot of approximation, the settled galaxy has approximately one settled world per 50 light year cube (about one per 125,000 cubic light years). If a map grid square is around 5,000 LY square and 1,000 thick, then each square has 200,000 settled worlds. Maps for the various RPGs therefore only highlight famous ones.
Okay, that gets a little overwhelming and that's why I think Star Wars is Space FANTASY. The Millenium Falcon's computer calculated a course, going 35,000 light years, dodging all the stars in between (which it has to have data for positions and vectors of all the stars in at least that quadrant of the galaxy!) in a few minutes. The Republic/Imperial Senate only has a little over 1,000 senators/representative groups. Then each senator would represent hundreds of worlds. EXCEPT that we have planets like Alderaan, Naboo, and Chandrila that have their own senators.
EDIT- Doing more research, apparently "senatorial districts" can be whole sectors or even corporate guilds. There was a Trade Federation senator in the prequels (I assumed the Trade Federation was a planetary trade group, but no) and a senator can come from a dominant world and represent others. I feel that is more sloppy worldbuilding.
This is why I hate a lot of pop culture TV/movie series from an author/gamemaster's perspective. Doesn't anyone do the math? Although, it could explain how the Empire can build things like the Death Star; that's a lot of tax money out there. It's a great setting to be a criminal in, there's no way wanted posters and criminal records could spread, there's just too many criminals out there to keep track. Just keep moving and your record could never catch you. That makes forgery of personal and ship IDs easy, no one could track all of them centrally. As long as your ID passes local inspection, you're probably good. Yes, they do it in that great scene in Andor, but I don't think that's realistic. EDIT- Hmmm. The Imperials might not have registration records from every backwater world but might have them from major worlds. Luthen picked a known, peaceful world whose records would be legit to throw off suspicion?
Another thing I thought about was that with the entire galaxy available, marginal worlds would only be settled for rich natural resources. Current estimates are there could be billions of Earthlike worlds in the galaxy. Sure, some would be unusable due to things like really nasty life forms or atmospheric or geologic hazards, but there should be plenty.
Traveller, on the other hand, has lots of marginal worlds because star travel is so much slower and shorter ranged (the Star Wars hyperdrive is around 45,000 times faster than Traveller's), you can only go system to system instead of covering vast distances.
Where does that leave us?
A million member worlds and 69 million colonies is just whacked. I'm going to try to proceed from the approximate 25K worlds that is attributed to Lucas and go from there. Even if that's member worlds, lots of those worlds would be too minor to have direct senatorial representation. There may be more than 25K with minor colonies that no one knows or cares about. There's even the line in The Empire Strikes Back; "Milord, there are so many uncharted settlements..."
BUT…Taking the quote attributed to Lucas and looking at how many map square grids the known galaxy covers, we get around 25,000 worlds spread across 280 map squares for around 89 worlds per map grid.
The map squares usually have around ten named worlds each.
NEW IDEA- First off, for the On the Rim campaign, players really only need to be concerned with their sectors and maybe surrounding ones. Second, what if change the size of known space? Instead of covering most of the galaxy, what if it just stretched from the galactic center to the galactic rim? Instead of almost 300 galactic map squares, it would be less than 100. 24K worlds across 80-100 map squares sounds better. That gives 240 worlds per grid square. And 100 squares with 8-10 sectors per tallies better with the 1,024 "seats" in the senate. So Bail Organa is the senator for the Alderaan sector, named for the most significant world in the sector.
UPDATE- I am sticking with the 25K worlds across the galaxy. The Ventooine sector has at least 24 worlds, but it is a sparsely populated area.
