If you want real size, go Eve online. In that setting, real sizes work. It would not work in Freelancer, unless you exchange tradelanes with system-internal jumpgates... and if not; Tradelane flight for 5 minutes is very optimistic *chuckles* it would take ages in real size.
But lets throw something else to it;
Even if it is POSSIBLE to alter the speed the tradelanes operate with (I never tried to do that)... every pirate faction other than Lane Hackers would be rather doomed, really... and every system not having tradelanes would be doomed either... unless you completely overhaul cruise engines... which is another effort of balancing to undertake... even if it is NOT real size and just "bigger", the initial problems I just stated remain.
To hunt the prey is life,
to lose the prey is death,
to hunt the loss is insane...
