A previous dev has recommended the GTA six map should be smaller sized and a lot more densely packed. Having said that, as leaks have continued to trickle from Rockstar, modders have recreated the GTA six map in GTA 5's motor which provides a way of its huge scale. https://gta-six-map53185.blogripley.com/36126226/grand-theft-auto-6-release-no-further-a-mystery