i haven t really read all - but just a few numbers:
the diameter of the sun of the sol system is around 138.000.000 square kilometers.
the diameter of the sun in manhattan is around 1 square kilomter
realistic measures are impossible ... and totally boring, too. we can assume that a tradelane may catapult the ship at lightspeed towards its destination. - we can also assume that manhattan may be ( in an ideal case ) as far from the sun as earth from our sun. the light needs around 8 minutes to go from the sun to earth.
soo - to get from manhattan to like california jumpgate ( which might be like 2.5 times the distance from manhattan to the sun ) - takes you around 20 minutes of utter boredom.
add to that that the game is a dogfight game ( meaning, its not simulating modern warfare, but rather world war 1 warfare in planes )
everything about realistic scaling gets down to become a compromise between gameplay and realism.
if scales were realistic - and we believe that the liberty navy deploys billions ( literally ) of battleships and cruisers - all the size of small cities - chances that they meet with the rheinland military in space are lower than winning the lottery 10 times in a row.