I love the clean, uncluttered look of your home and you've made some great furniture choices. My first thought, though, is that I would try to rework the sofa/sectional placement. It really is unwelcoming looking to me to have the back where it is facing a wall, when it could be oriented to look into the room and out the windows. It seems like if it were placed in the corner under the stairs that it would feel open and invite you to come in and sit. I'd hate to be cooking in the kitchen and have the family or guests with their backs to me. If you are having a TV in another room close by, do you need one in that room, too? If, so placing a 70" unit will probably only work as you have it. But, to me, it's not going to look like a living room but more like a movie theater, which is fine if that's what you're going for. It seems like it won't be a cozy conversation area, though. I might actually flip the rooms and put the dining room where you have the sofa now. I was looking at lights used with dining rooms and ghost chairs and saw this, maybe would work in the living room? Kind of fun. don't know if it would look as good without the colored walls though. And I thought something like these were interesting to consider for over your table:

What ever you do don't buy anything else black or dark brown for a dark room. Don't please, paint the room gray. So depressing with all the black/brown. Black-out drapes come in different colors. Paint the walls a pale linen color which will go with everything. Find a color you really like and use that for drapes and a few pillows. Look for a decorative piece for the coffee table. Use a tray with a colored candle and a small plant to give some life to your room. Get rid of the mini-blinds on the door. These are black-out drapes from Target. They block light but are not dark themselves.

Why so GA? I thought I hated fake fireplaces, but if I was going to have one, I would sure want it to serve the function of giving off heat . . . if I needed that. I live in the frozen north country. Otherwise, it is just something to dust to me. I also realized that if you live in a dark grey area of the country (I do), there is nothing wrong with getting artistic pieces that evoke the light and warmth of a fire. So much the better if you can chose sometimes to just have the light. My dad has one of those colored sparkly heaters in his basement, and at first I thought, "How gauche!" but when I changed my perspective and thought of it as a piece of art that not only pleases the eye but serves a function, I changed my mind. I don't much care for the look of a TV over the fireplace, and since I use my fireplace daily, I don't like thinking about how the heat would affect my electronics, but having a TV over the fireplace is pretty much ubiquitous nowdays, particularly in warmer climates. My comment was only to consider that I had a fake fireplace which had a SINGULAR purpose of being a decorative feature, and it took up way too much wall space to be practical for me, it was nothing more than something that was a pain to dust, and made me want the warmth of a real fireplace. It was too high to mount a TV over so mine was on a shelving unit to the side, but my TV was smaller than the huge ones popular today. When I bought the house it was a huge charm feature for me, but that faded very fast. Fast forward, my landlady once loaned me these big square space heaters to help with the heat in my un-insulated apartment. They had one function, to heat the room and were otherwise ugly black blobs. Here's a photo of my fake fireplace. A lovely white elephant. I did not think so when I bought the place. Of course YMMV, just giving you the perspective of someone who lived in a tiny house with a fake fireplace for 12 years.

I like the pattern fine, although it is not one I would choose for my home! I am more traditionalist. What I do not like about those two: fringe, especially light fringe, gets noticeably dirty where it is in the walking path. The same goes for the light colored background. This will be in your main space, and in the walk path from front room to kitchen -- I would look for a version that minimizes the light colored areas. Unless, you have no problem with frequently cleaning it - it needs to be colorfast also. I hope you have a couple of days off now to recoup. I used to do eight 12 hour shifts in a row every month (for child care purposes), and often found that I was more prone to coming down with something afterwards. My unit has been converted into the COVID-19 isolation unit for the hospital.