Upgraded my ships's navigator from rank 4 to rank 6, so that's 2.5m more spent
on the ship. Speed boost is noticeable at least on tradelanes, rank 4 spent
2:44 running from Lucentium to Furnachia, and rank 6 spent 1:49. Speed wasn't
the reason for the upgrade though, but to be able to set longer paths. Maybe
now I can start using the ship more widely as a regen spot.