The current system of housing items is not working well. Currently, the first item gives full value, the second gives 75%, the third 56%, fourth 42%, and so on. It doesn't matter what the items are. The problem with this is that the order in which you place items is important. Placing a 2-point item in a room of 1-point ones will give less if it is placed third instead of first. And even if you do place it in the correct order, sometimes it will randomly change.
When looking this up, I came across information that said the 75% decrease was applied to item types, so having two chairs would not be as good as a table and a chair. This was obviously changed sometime and I think it should change back.
Also on the subject of housing values, the balanced house multiplier breaks the whole system. There are times where placing a new item will decrease your overall score, significantly. This should never happen. If I spend resources I should get a benefit for it.
My suggestion to fix this, and still take balanced houses into consideration, would be to change the amount of points given by an item in relation to the current score of the room relative to the other rooms in the house. The lowest value room should give the full value for the item.