The increased il is there so players can group up as 8 if they want to tackle them.
Number of rooms would change much it would just be 7-9 rooms max a run. Going down a floor teleports you in the same room but it isn't cleared. Which gives you another chest without having to open a door and risking rng with opening doors.

il180 really isn't that high. Alot of people are way above that and even when next normal alex comes out & the patch its gonna go to 250/260/270 item level. il240 gear will be nothing by then when add in this.