The game is not ugly, but it's never really as awe inspiring as the height of soulsborne, nor is it as creepy. It's just not particularly evocative atmosphere wise for me. I felt awe when I saw locations like Anor Londo or Drangleic Castle. Catacombs and their darkness and ease of falling induced stress. Places like Irithyll Dungeon or Yahar'Gul achieve a height of creepiness that Ashina's dungeon or depths really can't. And it's not like Sekiro wasn't trying, despite its Sengoku Japan setting, considering the presence of those undead looking things you need to kill twice, people who attack you with their centipedes, those things that attack you from the walls in the cavern inhabited by the giant serpent, the insanity of the people in Mibu village etc. It's just pretty lame and the mechanics of the game encouraging you to feel safe at all time and jumping from roof to roof and branches doesn't help. The constant use of soundtrack during exploration despite the soundtrack being pretty.. average? wasn't particularly bright either for atmosphere.I wouldn't say levels are boring, they are good but From sure didn't outdo themselves. Stuff like Mt. Kongo or Bodhisattva Valley - visually awesome but not the pinnacle of complexity. Remind me more of the Dragon Aerie than anything else. Another Blighttown or Undead Burg they are not. Plus an idol every few steps, as if we can't have a real chad game in 2019 anymore... A bit disappointing.
Overall, it's the first From software game that thoroughly failed to attract my attention during exploration, for the whole duration of the game.