Rendering pipeline is insanely overloaded in Amnytas and Wizard's Tower due to how detailed environment and not properly working culling. In some places even when structures are obscured from the view, they are still impacting fps when camera is facing them. Its extremely visible in amnytas where basically entire map is a city.
Setting Environment to Low from High / Medium gives 20-30% fps boost on a new maps in some places. LOD Distance also helps, I lowered it to medium for 5-10 fps increase in the worst performant places in the Wizards Tower. Just remember to relog after changing it because LOD does not apply instantly otherwise.
Unfortunately, visual cost is noticeable, especially when changing environment to low