I would have liked to see biped construction be more like lair shaping - not just in the modular approach, which is far superior to the static structures bipeds get, but in the complexity and sub-assemblies that are required. Making stone bricks into smooth tiles and foundation supports, then combining them into stone floor units which are then applied, for example, would be a lot more interesting than collect bricks, make blocks or keystones, and apply.
Maybe it's just an immersion/RP thing, but the names and descriptions of lairshaping resources and the logistics involved with making them feels a lot more real and satisfying than biped construction ever has.