To make the scales correct would mean the average person wouldn't be able to see the ships on the field - even huge ships aren't that big.
For example, Star Trek's NCC-1701-D USS Enterprise had/has the same number of people on board as a modern aircraft carrier does.
Even in-game descriptions list max ship size as anything up to 2 or 3 km long.
I imagine it would lose more immersion factor than gain any...