You are looking at cultivation efficiency, why are you doing it outside of your array and making it harder on yourself? The element matters when cultivating, and that's what your inner disciples are going to be spending most of their time on. Now, looking at an example of what the elemental rating of a proper room looks like.
This is taken with the Feng Shui view and looking at the center spot where the Cushion is at. As you can see, the Earth element is over 90%(94%), making it pretty obvious that the location is full of Earth element.
Metal One is a cultivator of the Grand Chariot Wisdom Law, so based on my previous statements he should be pretty satisfied in that location. And so he is. What his bedroom looks like, I don't care, since he spends his time in the cultivation room.
Also, you need to understand the difference of 3 groups, Feng Shui Nodes, Decorations and Items on Display stands.
Feng Shui nodes, Beds, tables, Qi cushions, take in elements, but they don't radiate it.
Decorations, like lamps, vases, radiate their element better than items on stand but don't gather Qi, making them useless for normal cultivation.
Items on display stands, especially those that gather Qi, radiate a bit of their element but improve the Qi gathering of the location based on their stats, making them useful for normal cultivation but useless when trying to improve the Feng Shui rating.
For a bedroom, you'd want beds and decorations.
For a cultivation room, cushions and items on display stands.
The wiki page on Qi gathering has some info as well:https://amazing-cultivation-simulator.fandom.com/wiki/Qi_Gathering