I like the dark gray, which is what I was going to suggest, but you've already bought it! The pillow looks good too, but you could also have gone with a soft gold, which might be hard to find. If you can get an ottoman in a matching fabric I'd go for it. Especially if you read or relax in this room a lot.

IMOa lot depends on budget. I too like BDI but not in any way cheap and I have found many of their TV credenza too high for proper viewing height. My go to for a decent price is Ikea Besta and it can be configured to not only give you a TV stand but also some extra storage and display I actually think some wood might be a good choice for a finish with white. You for sure need art and IMO a much more colorful rug and maybe look at a Noguchi table instead of that coffee table table

When I saw the kitchen, I had an immediate different thought than I see here. Is that formica? If so, I would replace it with new formica in a different color... This is not a major job, evidently. It comes with the backsplash and everything. You just order the length you need. Grey (as in one of the photos upthread)? Navy? Black? With the teal blue chairs, one or more of these colors on a countertop would be striking.

I like pieces that are not matching though I find myself drawn to more classical styles such as the two Chesterfield loveseats in emerald green velvet, a wonderful wing chair in a kind of soft, almost sage green, and a rich cream sink-into-it chair and ottoman. The lamps are a mix of table and floor and modern and traditional. I would suggest looking at various styles of sofas online and getting a feel for what you like: straight or rolled arms, low or high arms, loose pillows on the back or none, and so on. Once you have narrowed down your choices to fewer than five, go out and try them out in stores. You don't have to buy from the stores but you'll get a strong sense of comfort. At the same time, think seriously about your wall color. You may want to stay with a neutral to allow a brightly colored sofa to stand out. Or maybe a dramatic color with neutral furniture (black paint, rich cream furniture in different textures and subtle shades). I definitely agree with no matching sets of furniture. Based on what I said at the beginning you can probably tell I ignore the advice to go neutral with the bigger items and bring in color with accessories. I love it because I took my time to discover the color I truly love and never get tired of: emerald.