If the price of the freighters will remain the same I see a small problem.
Civilian Freighter has a cargo of 540, if you double it you will get 1080 - guns, shield etc and the ship costs 1,784,170 credits.
Mammoth has a cargo of 2200 - guns,shield etc and it costs 10,114,750 credits.
So it will reduce the gap between ships and make some ships never flied I guess.