I think everyone's gotten frustrated when a freighter doesn't set a trade route that optimally uses the already built economic starbases.
Lets say Planet Alpha and Planet Beta are 20 spaces apart, 15 diagonal spaces and 5 vertical spaces, and that a starbase covers 8 spots in this route. Sometimes, the AI will design the route so the freighter turns early or late, preventing it from using as much of the AoE as possible. For every time the frieghter turns too early or too late, it'll miss about 2 spots per run (a big difference starting at 5 weeks). Is there a click and drag function or something of the sorts that lets you adjust or bend trade routes?