The original poster said "The use of equal negative space, as a balance to positive space in a composition is considered by many as good design." Does it need to be equal? What is equal? Think of two flower beds on either side of a grass path. In your mind keep the flower beds the same size and start widening the grass path from very narrow to very wide. There are clearly extremes that just don't seem balanced. But there seems to be a lot of middle ground that looks just right. If the plants are short you have a lot of sky - also a negative space (or at least I consider it negative). Making the plantings tall reduces the visible sky, reducing negative space. I like to think of this in terms of the light - dark concept. You need light to see dark, and you need dark to see light. The 'amount' of each can vary dramatically and still give a contrasting and pleasing effect. In a garden the amount of positive and negative space varies as you pass through the garden. Think of walking towards a tree. At one point it is almost all sky and the tree enhances the sky. As you get closer, the tree becomes dominate, and the sky now enhances the tree. So maybe the main point is that you need both positive and negative space, and that the best design is one where the ratio of each varies, relative to the visitor - to keep things interesting.

Our living room is like this: http://imgur.com/a/mlsYT The dotted lines are area rugs. The sofa is 3 piece with chaise on the bottom left side of the image. That is a bay window on the bottom wall. The door is on bottom right and that entire right wall is is foyer/entry that we want to continue as such into kitchen. Perhaps one day with half wall / ceiling like this: [https://www.houzz.com/photos/oliver-street-traditional-entry-vancouver-phvw-vp~468274(https://www.houzz.com/photos/oliver-street-traditional-entry-vancouver-phvw-vp~468274) The bay window and sofa are both about 8.5 feet side. Another 1.5 feet on each side (to door and to wall). The opposite wall is entertainment center. The left side wall has a single window. Anyway, the image shows the sofa with chaise on the left. However, I am realizing that this only allows for 4 (maybe 5) people to comfortably seat without being on an ottoman or the floor. So I want to add another chair. Something that swivels and can be essentially opposite the chaise section. This would allow it to face the sofa/ottoman for conversation and swivel around to watch TV. Far forward and to side enough to not block anyone from sofa. It isn't ideal that it overlaps the sofa but think it should look okay? If this chair is put in while chaise is on left side again wall... well now there is a chair floating adjacent to foyer. The opposite puts it adjacent to the wall with window. This seems better but don't know. Not sure which would look and flow better. The chaise by the foyer requires walking around it. If half wall is installed then it means extending that further as well. But the chair near the window seems like a better spot than floating... ? If the chair floats near foyer it does still allow you to walk around either side since we won't put it too close to sofa. But walking in and seeing the back of the chair while it's facing TV could look awkward? Less awkward if facing sofa but still not sure. Would love opinions on this. We ordered sofa without thinking about this and now I want to make sure we figure out the best solution.

A 3-seat sofa and two armchairs are usually the most flexible for arranging and then rearranging. With TV on the long wall above a credenza 25% wider than it, you can float the sofa with its back to the dining area to create a division. Add a sofa table behind it that can function for both areas. Then you'll need a coffee table. Place the chairs facing each other over it, right and left of the sofa. If you can find swivel chairs they'll easily turn to watch TV or back to conversation. Then move on to lamps, etc. Do you have any floor outlets or are they all on the walls?

I can’t read your measurement, so counted the squares as one foot each. There are a few options for furniture arrangement, but I think purchasing a sectional will be a one way street for you…go with a sofa, or two sofas facing each other and two chairs side by side facing the fireplace.