During Ben's weird period, this is one of his things that comes out of his mind(during a meeting with Hank):

"Do you think the furniture in this room is arranged
adequately? I've been toying with the notion that if one
could find the proper spatial relationship between all the
objects in a given space, it could create a resonance the
benefits of which to the individual dwelling in that space
could be extensive and far reaching."

I've often noticed the way DL arrange furnitures on the sets in his films - tables and lamps - symethri.

I wonder if these words of Ben are actually Davids own thoughts. Ben retutns to the world as a pure human being; carrots and nature - holy books - wanting to do good, be good.

Ben had to be broken down, and at his lowest - a perfect resonance occured in his mind and soul (DL's yoga), and he was reborn.

Any thoughts?

Is DL describing a way to create "peace in mind" or is he actually litterally on this subject; that you can create some sort of power/resonance by arrange objects around you?

Is there symmetry in Lynch's placement of furniture?

With the scenes concerning Ben, I doubt Lynch had anything to do with those scenes. Look to who scripted the episodes.