I can not get more then 100 million people pre collapse no matter how many times I reroll, anyone else seeing this?
I spent a *lot* of time rerolling because I wanted nice, densely populated planets.
You want, in order:
0.9 to 1.0g gravity (not above)
12-16°c average temperature (not more, maybe down to 10°)
at least 10% oceans
at least 800mm average rainfall, and ideally over 1000mm rainfall, this is the 2nd most important signifier
an atmosphere described as "earth-like"
all of these ingredients give you a chance to roll very densely populated pre-apocalypse planets (my record, so far, is 3.5 billion in 121 settled zones)
of course you still won't have more than 2.5 million people post-apocalypse and never enough population to actually get a tier V or higher city, but you'll have a lot more fun with ruins, I promise you that