When you design a ship it's normal to start with the overall shape or form, and then noodle down to details, perhaps dividing the work into sections or functions, according to the needs of the story. Think of the movie District 9, with its mothership floating in the air above Johannesburg. The overall form is a tube, but in the story there's a docking port where humans board to find out what's going on, and a drop-ship clamped under it that becomes the escape vehicle in the end, so these areas got a lot of extra attention from the designers. These are the notes from a concept artist who worked on the drop-ship in District 9: "Bevel all angles", "Many subdividing panels", "Body work is thin plates over thicker structure", "Far more mechanical structure [visible] in transitions and gaps", shown in The Art of District 9, a book by Daniel Falconer of Weta Workshop.
Artists who do a lot of 3D tend to get used to explaining the features of a design in terms of the tools...