Do understand that the game underwent 2 MAJOR catastrophes in development.
First, when it was just Shibuya as Director, DaS2 was going to be an open world game. early concept art specifically shows vast distances between the CU and the destination. They make a big deal about the game taking place on the whole continent of Drangleic.
Bamco decided they didnt like that and told them to make it more like Dark Souls 1. At which point, Tanimura was inserted as co-director, and they had to completely reimagine everything, but without starting from scratch because they didnt have the time. From there they also ended up having to downgrade the game and rush it out.
So you have some poorly connected areas, like Earthen peak to Iron keep, where Earthen peak was originally going to lead to the undead crypt, where the Rotten was going to be the boss. (which is why EP has those crypt guardians) Harvest valley was originally about you activating windmills to blow away the poison fog, not burn a windmill.
Amana would have led to Shulva, and the Dragon Shrine would have been the actual Castle Drangleic. Something painfully obvious from the intro to the game, which was clearly made very early before the development troubles.
in all this is the torch and lighting mechanic. DaS2 has in many areas, dynamic lighting of some sort. So, certain areas would be pitch black and need a torch to traverse. It was a gimmick. That hallway in the forest, and also The Lost Sinner, who is clearly meant to be in pitch black darkness to sort of motivate you to do the gargoyles for the key to light the room up. And the Gutter. The lighting was scrapped because lolconsoles, and so we'll never know what the game with the original lighting wouldve been like.
Personally, I'm of the theory that DaS2 was originally meant to be on the PS4, but that Bamco made them push it back onto the last gen so it wouldnt have to compete with Bloodborne.