This will be my last suggestion before the game is released
It's something I briefly touched on before on the steam forum but I figured I'd put it in word here too. Once more than one galaxy has been created it's increasingly difficult to remember what goes on in which galaxy. Emerged/Extinct races, relation modifiers, diplo changes, etc... If the system is more likely to create the same races in the same galaxy, like it's implied, that sort of stuff too.
It would be nice to have some way of have access to that information in the game, preferably on the Set Up Sector screen.
There's any number of ways that would be good to show this. Perhaps a variation of the existing Planets Screen that can be retrofited, or a new screen altogether.
I made a mockup to show you what I mean:https://i.imgur.com/OxKSzkr.png