What better way to invest in your own settlement then to network with other NPCs from the same or other planets. Plus expanding your own settlement to house traveling merchants or companions would be a nice way to encourage people to actually want to go back home. These implementations would also make room for more achievements such as making a city for 10 or more NPCs or establishing 3 or more trade routes with other settlements.
I guess the best way to start towards this path would be to add some interesting NPCs with programmable AI such as telling them to look for resources, make thi