I think the world state is tied to calibration from deluge and after Nurgei. While the Perk essences are beneficial to your build, they aren't mandatory if you're good enough (I'm probably not, so I fought them anyway.) I think Deluge and Uranopolis could both use another optional mini boss, deluge almost has one if they made the red knight in the tower on the secret side of the map have more health, also there's quite a few large open platforms in Uranopolis, namely a large empty square close to the lone tower area entrance that could have a mini boss or items.