For the true megafreighters, I envision them as pure skeletical jump frames where "smaller" (I'd say up to 1000 dton) barges able to land could be attached. For regular routes, the jump frame just arrives to orbit and the barges dettach and land to be unloaded, while similar barges already waiting loaded in the world attach themselves to it and it's ready to go away again. That way all interface is "self contained" by the company and the loading/unloading could be done dirtside, so shortening the time the jump frame must be in orgit to th time for itself to refuel and for the barges to dock/undock.
To save in ship crew, the barges could be crewed by people in the world and make the roud trip or even be robotic (no crew at all), and each one being a self-contained boat.
Even some of them could be passenger carring, so slowing the time for passenger boarding and, if swaping jump frame, you'd be able to go a whole route in the same barge even if the barge itself has to swap frame several times along the route.