Region: The Milky Way Galaxy
The amount of realism (or lack thereof) largely depends on the individual player. Speaking for myself, I tend to be hyper realistic in with regards to planetology, astronomy and stellar cartography. Furthermore, biology and all that that entails is also based on hyper reality. Technology is different, as I use FTL (which is ubiquitous for most), while others I've seen are hyper realistic in this regard. It boils down to what one feels comfortable with.