The world generation rules will remain flawed until the crucial last step is added: The Vetting of the UWPs. The reason for this is that as long as you just generate a bunch of random worlds and scatter them randomly across a map, with no regard for how they affect each other now (and just as important, how they have affected each other down through history), you're going to get... substandard work.
Someone needs to go over any new set of UWPs and adapt them, not only to reality (cutting the number of really unusual worlds down to the point where they are, you know, unusual), but to the neighborhood.
Say, for example, you have several well-populated worlds and notice that a particular empty world with a class E starport lies very conveniently for a transshipment point. "That's strange," you muse, "how come no one has set up a warehousing operation and maybe a small ship repair shop there?" And the answer would be different depending on the historical period.
* For Milieu 0 the answer migh be: "That's easy. Interstellar traffic in this area is pretty recent and no one has gotten around to setting up such a facility yet. In fact, I don't even think the Scouts would have set up a spaceport beacon here; I think I'll change that starport class to X."
* For Milieu 200 the answer might be: "There was one very recently, but the colony got wiped out by the Purple Polka-dot Plague. No one's going to set up a new one before they've figured out a cure. In fact, I think I'll redzone it; the Imperium has surely slapped a quarantine on it."
* For Milieu 400 the answer might be: "That is strange. I think I'll up the starport class to C and make the population... <rolls dice> 700. No need to roll for government type, it's an outpost of <checks map>
that world, which would give it a captive government."
* For Millieu 600 the answer might be: "There was one very recently, but the Zhos wiped it out in a raid. The starport was thrashed, but the Scouts put in a new starport beacon. Maybe I should put in a population, though... secondary population living away from the starport and thus surviving the attack. Whole infrastructure is ruined, of course, so government 0, but they still have their equipment, so the TL is roughly the same as the mother world -- maybe a level down."
* For Millieu 800 the answer might be: "Maybe the whole colony was revealed as a secret psionic community... NO! Bad Hans! No bisquit! You've used the secret psionic community four times already! Give it a rest! OK, so the outpost was reestablished shortly after the Second frontier War, and it's been growing for 180 years. And don't forget the original population... 3% population growth per annum... almost 100,000 inhabitants. Still a captive government... there's gonig to be trouble one of these days..."
* For Milieu 1000 the answer might be: "Another 200 years of population growth... better tone it down a bit... can't make an empty world into a high-population powerhouse... call it 5 million inhabitants. Got their independence a while back..."
* For Milieu 1100 the answer might be: "Maybe a meteor wiped out the entire population...? No, I've used that before... and there's Paya... and... I need a new idea... <tears hair>... Aaaaaaarrrgggghhhh!"
Hans