Floor after floor, but I also have to work on a whole bunch of new maps for the inbetween of floors. The road connecting Tolbana to Floor 2 has a total of 15 maps (currently working on one of those, which contains a boss encounter called "the Collective". (just to be clear you're only required to pass through 6 of them to get to Urbus, they branch out a lot).
It's related to the same philosophy of lengthening the dungeons, like I did for Illfang's: Much of the challenge comes from forcing the player to travel continuously with dwindling resources.