Additional docking points and special commodities would put the freighter into a pretty singular niche and given the lack of popularity the current satelilte points have I'd wager not a very successful one.
I would suggest adding "fighter only" jumpholes instead, ones connected in such a way cuts down travel times for blackmarket stuff and other questionable items (refugees, fugitives etc) giving people choice between slow bulk profits or short quick cash-ins. Keep the balance against fighters and we have ourselves a fun little dynamic and if a few freighters are remodelled into piracy ships (perhaps paired with a bomber?) it could potentially boost cargo piracy, depending on how the aforementioned jumpholes are laid out.
