My update later today will address some of this, but the gist of it is that now that we have started actually laying out the book in InDesign there are several things that have become abundantly clear to us in regards to content that really should just be removed from this book in order to make it more approachable, both for new and experienced players alike.
Now, in regards to the map generation and star system rules, those will be staying simply because they don't represent enough content to warrant porting them to their own book. The "flipping back and forth" effect would be a pain in the butt, and it is just easier to present them alongside all of the other options. Also, as far as page count goes, the Universe and Galaxy map options don't take up that much extra space, and I expect that most "mid-sized" VBAM campaigns will actually use galaxy maps to at least track the location of sectors on the map.
The advanced star system and planet rules fall under a similar umbrella of being not enough extra to warrant their own book. It is just easier to give players all of the tools in that particular toolbox rather than try to awkwardly cram them into a followup book.
That is not to say that I haven't seriously debated deferring the System Map rules to another book, but that requires that the interplanetary lane be deferred, too, and then you end up with solitary jump lane types just sitting in isolated source books that you can never remember the location of. So consolidation is key here.
As for the star system rules, I will admit that the star generation rules take up a bit more space than most would like. But, again, it is easier for the rest of the rules to have them be present.
We are pulling some other rules, which I will discuss in this afternoon's VBAM update. And I may still be convinced to remove some of these other rules, but right now I am thinking they are going to stay.
-Tyrel