I dont think construction needs to be made faster. I needs to be of higher quality. ( Ignore the land issues for a moment ) You could built a 60 floor Skyscraper in less then a month.
What we need is a much faster, semi / automatic way of internal renovation in each floors. Door, Glass Fitting, Pipes and Electrical Wiring etc.
And all of these needs to be of high quality finishing. Taking into account of Temperature variation, lighting. Making building with the precision level of a Smartphone.
Even today, you could see building with Windows not aligned perfectly, floor line running slight wide, floor not perfectly level. Or even Windows with Leaking Water.
May be all of these are specific to Hong Kong, where we paid the highest price per Square Feet in the world and get absolutely dismal quality of building.