Logistics ships

Players can construct freighters from any available capital in order to move pre-positioned parts or other useful things (like fighters) from one place to another. Such ships do not count against the initial 4000 pt cap on military vessel construction, as long as they are not armed with anything more than 1 PDS or class 1 beam per 10 hull boxes.

Freighters can be as stupidly big as you choose. If they're big enough, they can carry actual starships. Mind you, if someone does this, they've either won or they're about to lose.

Subsequent conversion of cargo spaces into fighter hangers or weapons racks costs 20% more than normal (because the engines cannae take it without extra strengthening brackets).

Freighters don't manoeuvre better when they're empty than when they're full. It wouldn't be economical.