What the brief decides
Framing system. Wood, cold-formed steel or a hybrid, decided for your project and not in general: the fire zone, the seismic category, termites, the schedule, the crew that will build it and the budget. When steel wins and when wood wins, in writing, with the reasons.
Concrete and foundation. The mix class the job calls for, where a lightweight or high-performance mix pays and where a normal one does the work, and the foundation system matched to the soil report and the seismic category, with the geotechnical and structural engineers who will stamp it.
Performance upgrades that compound. Non-combustible assemblies in a fire zone, seismic detailing, a moisture and termite strategy: the home resilience line, specified at the level of what the house is made of.
Prefabrication and procurement. Where panelized framing and pre-wired assemblies save, and at what scale; where a one-off house gains nothing from them; import sourcing for door systems and fixtures with the duty and freight math done in the open.
The cost direction of every line. Each recommendation says which way it moves the number and what it depends on. A line that cannot say that does not go in the brief.