By playing the game I noticed that i can't use ladder to climb up a building, but it can change the game by logic and with that tiny detail, by adding a use to it, we know that ropes can be broken but ladder can't be but they cannot be move to except by being broken with a masse because it useless in the game.
The ladder will give less fatigue than a ropes and if you are tired you will climb it much slower (but less slower to ropes)
it will downgrade ropes but it very logic after all
(and for the helicopter i won't ask you to add a rope ladder but i will give a reason to why they don't do it, you can be infected and you can cause a big danger to the pilot, because you are in the exclusions zone (and for realism you can add crashed heli of the pilot who tried to save survivor that has been bitten to reinforce why they don't help us in the game)
and sry for bad english i'm still learning it
