"Ungrateful little shits who die off and get pissy when you ask them to work hard labor on a shitty planet." - Anonymous
Colonists are your most important asset. They work your buildings, crew your ships and fill your coffers by paying taxes.
What you can do for them
Colonists are just people who live at a
colony. They need to eat, they get sick, they want to have fun, etc. Their basic needs are usually filled by the private sector as far as that is possible and profitable. As a benevolent ruler, you can do better by running government sponsored
facilities. A well run colony will attract more immigrants, improving your overall capabilities.