So here's my rough idea for how you could basically send one large ship with a crew of a few thousand (at least ten thousand, maybe forty) to establish a colony on an Earth-like world:
First step is to build a ship. For the purposes of this thought experiment it will be an FTL ship but this is honestly inconsequential. The ship should be a few hundred meters long and shaped like a football with two segmented tori attached to the main shaft. The bulk of the ship will be used to house food, supplies, and the 10-40k freeze-dried (obviously not literally) colonists, who will be hibernating for the vast majority of the trip. The tori meanwhile pull double-duty as warp drives and as prefabricated hab modules.
Second step is arrival. Upon reaching the planet, the ship will decelerate and discard its tori, which will break apart into their individual segments and begin a controlled descent into the atmosphere with the aide of parachutes. The ship itself, meanwhile, will allow gravity to do its job and take it down to the surface ahead of the modules, for reasons explained in step 3. Once the modules have reached a safe speed and height from the LZ, the parachutes will detach and the modules will drop. Once they've landed, they'll begin automated self-assembly into various utilities like habitats, drilling platforms for mining, storage units, generators, and ideally a functioning power grid.
The third and final step is actually clearing the LZ and properly positioning your modules. This is why the main body of the ship is allowed to descend faster than the modules. Once near the surface, the ship will engage its retrorockets to rapidly decelerate. The resulting heat and thrust will clear the immediate area around the ship of vegetation and other obstructions, and on an oxygen-rich planet like the one in my story, the resulting forest fire will hopefully clear not just an LZ, but burn down a large enough area of forest to begin establishing a proper city or town, with the main shaft of the ship (now embedded into the ground like a skyscraper) serving as its center. With the area thus cleared, the modules can descend and begin assembly of the colony infrastructure on clear, open ground.
Does all of this sound feasible or logical? Are there any blatant violations of logic or physics I should be wary of? Most importantly, would the forest fire caused by the descent of a spaceship onto an oxygen-rich planet merely clear a few kilometers of forest as planned, or would it spread out of control and scorch a much larger area?