The existing Muni lines would be sufficient to transit a large capacity of the Outer Sunset residents into downtown if they were given signal priority. The recent proposal to create a dedicated 2-3 car Muni subway line which Sunset residents have to transfer into at West Portal station is itself a huge improvement. Studies have shown that a large majority of Muni delays can be explained by the fact that trains share road space with cars that often obstruct them (and increase railway maintenance costs). Surface trains going into the subway make the problem worse, because an effective subway relies on reliable and precise train timings, but surface rail is unpredictable like a car because it shares space with cars.

The building likely doesn't have a roof deck because code and planning make that a very expensive proposition. Due to more recent planning code changes, roof decks under some circumstances count against the number of floors of housing you can build, so a builder is trading off units they can sell with the amenity value of a deck.

SPUR has an Ocean Beach master plan which you might find interesting: https://www.spur.org/featured-project/ocean-beach-master-pla...