[quote=@Keyguyperson]
So... how did this affect space travel? Do we need constant acceleration now? Are ion engines oddly powerful? Is there a giant ocean of plasma that connects the planets and systems? Are intergalactic trains now the only way to get around?

Also, we're being insanely pessimistic about technology and the number of habitable planets if the population of Andromeda and the MWG combined is only 3 trillion.
[/quote]

Not really pessimistic, as to say that Empire of Sol has a few very large populated systems, with small other livable planets put throughout the empire. As for getting around, the ability to go light speed and much faster has been achieved, and portals/wormholes are also an easy use for transportation.