The rail gun now not effective to any more, almost no one want use it because:
dam/s: medium
rate of fire: slow
spread: high
overheat: easily overheat
project tile speed: medium
range distance: medium
This is classic weapon, like its state above it should be put in the museum.
So my suggestion is:
Range: it should be the weapon have longest range int this game, try thinking if you throw a object in space it will move forever until i hit some thing or some thing make it change the orbit. all rail gun should have at least 6000-8000.
Project tile speed: base should be 6000+.
rapid fire rail gun: it rapid fire? it short range, slow rate of fire, project speed slow too very high spread. Should replace it with some new weapon? or just make it more effective to hit.
PS: sorry my bad english.