I kinda like the contrast between the environment and the characters--it seems like... thematic? Can't quite place the word xD It kind of emphasizes the feeling of being a stranger in a strange land. Everything kind of has this post-apocalyptic/haunted feel, despite being so bright and cheery and natural. Maybe that's just because they haven't shown many NPCs and towns, but yeah.

(Isn't that kind of what they did for The Last Guardian?)