Sketch idea for a small colony ship. The idea is the ship enters the atmosphere, discards its detachable heat shield (which lands a reasonable distance away with a controlled parachute fall, so its material can be recovered later). The ship lands and the ring on it becomes a premade perimeter wall. The variable arms holding the rest of the ship adjust and lower until the bottom of the center is on the ground. Heavy cargo and prefabs get moved out. On top, the large space engines detach and are briefly piloted as independent vehicles, and landed next to the colony to be repurposed. The flight pad on top of the structure is extended and supported with an additional strut. This initial colony is a little cramped, but a good foundation that is built to be secure, able to support air traffic, and able to support basic agriculture. I'm picturing it being several families worth of people.
Just something that came to me last night while trying to think up unique ships and tech.
The heat shield can double as protection from interstellar debris in slower than light voyages (if your world has no FTL). Karl Schroder's Permanence has interstellar ships called cyclers that have a design like this (for that purpose). The cyclers don't slow down and just cycle around on a preplanned route, coming by a given system on their route every few decades - centuries. They can eject cargo at a star system as they fly by and the locals can accelerate up to trade or what ever.
What fuels your ship? How long are the voyages? How do the crew live aboard?
There is FTL, which is accomplished by creating a field around the ship and jumping point to point. It's not unlimited, as there are certain points that can only be accessed from certain other points. Not to get too down that path but it's very ley line and new age crystal kind of logic there.
However, the colony ships themselves arent independently capable of FTL. They are slaved to an FTL capable tug ship and transported to their destination. This is done on a contract. Colony ships are built to order, almost always as part of a larger colony contract that includes initial survey, customized colony ship modifications, transport to the planet, landing the colony ship, and setting it up.
There are living quarters, however those are mainly meant to be used once the ship is landed. The ship is skeleton crewed by contractors (usually from the same company supplying the FTL tug ship) during transit. The contractors specialize in these jobs so they land the colony ship. The actual colonists, along with more contractors, are passengers on the tug ship. They come down to the surface after the colony ship has landed. There is an initial period where the contractors help with initial colony set up, such as detaching the colony ship main engines, adjusting how the ship sits on the ground, securing anchoring, and other tasks. The colonists while usually containing some flight certified members and mechanical engineers are not subject experts on landing colonies or setting them up.