Why does it matter to model the real terrain and real neighboring buildings?
Most aspects of a building are affected by the surrounding context. For example, sun access, wind and noise level. If the buildings nearby are skyscrapers they will limit the sun access of your neighbouring building and may increase the wind speed felt by users (to a point of discomfort). Noise levels is directly influenced by the nearby road of even the users of nearby building (i.e if it is an industrial park with numerous incoming trucks vs a quiet little neighbourhood)
Shadowing, noise and wind speed are only visible when context is present as without content it is difficult to know how the building would run in the real world.
Should the building adapt to the site, or the site to the building?
Whether the building should adapt to the site or viceversa largely depends on the professional being asked.
From a developers perspective a building should adapt to the site as they may encounter issues when constructing the building such as building needing to be built on a hilly land but was designed for a flat road.
From a designer’s perpective a site should adapt to the building. This is because the designers are the creative minds behind the building so they do alot of work to ensure the design meets clients needs and so they would be keen to ensure that the design is carried out exactly despite site context. From a developer's perspective?
◦From the perspective of the neighbors who already live there, a building should definitely adapt to the site. Inability to do so may cause extra construction to make site fit building, heavy shadowing unto the neighbours’ buildings and increased wind speed felt by existing neighbours. This will cause extra noise and discomfort to neighbours.
You generated three proposals and recommended one.
I technically chose because in my mind I had worked out that Option 2 would fix my noise level issue. It turns out the number agreed with me! Albeit not exactly as I thought it would for the noise level (only slight decrease in comparison to Option 1) and surprisingly (as I had not thought about it) even better sun access throughout the year.
I would have had to see a dramatically worse noise level and sun access to abandon my idea. My recommendation will still hold in 3 years as it is constructiblly sound, the weather in Napa is quite stable and I don't see the road usage changing anytime soon.