Keep merchants at the station, in rotation.

[LovelyMimic]

I would love this. It could be as simple as the merchant exiting their shuttle and moving somewhere a little more convenient for the duration of their time docked with the station.

It would also help if the merchants in question weren't selling pathology stuff what feels like half the time, since it is vanishingly rarely that anybody cares about that, let alone enough to spend money on pathology equipment upgrades.