In the last picture, does the door on the left lead to the garage? So will you be leaving the tile floor there? I wonder if you can't leave the living room arranged the same as it is now, but with the chair where the tv will be vacating? It doesn't seem to bother you now to watch tv on the angle. Although, since you are losing the half-wall, you can just put the sofa across the room, between the kitchen and patio door. That creates a walkway along the long wall. This is how we had our FR arranged, though where you have a bookcase on the right, we had doors to a powder room and a laundry. If your new sofa won't provide enough seating, add a swivel chair or two, either in an L to the sofa or by the bookcases as you have now.

I would suggest moving your large television and its stand from its current position to in front of the fireplace opening. This will enable you to shift the couch so that one arm of it is against the wall looking out the french doors, one side still have its back to the kitchen table but people can enter the couch area from the French door side. You don't want to block a fire escape route. When family comes over you can put chairs in front of the fireplace bookshelf and tv corner cabinet and the french doors. With this new configuration you can install a large fancy or plan rectangle decorative mirror on the wall above the couch to bounce the light reflected from the french doors directly across the space. People feel uncomfortable with their backs to a doorway or other people. You need to add a console table and lamps or a dresser that is short and long to go along the back of the couch to create a protective feeling for people sitting with their back to the kitchen. For future renovations to the space you could install bookcases flanking the fireplace with windows above the bookcases or instead of windows mirrors that look like window. This could be as fancy or simple as you like. Disregard tv above fireplace in the image below put a mirror where the tv is to bounce light around the room and put the tv and its stand in front of the fireplace box so you can still use the mantel and when you want the ambiance of a fire you can have your tv project that image. Here are some pictures. I like the warmth of this mirror better than cold black but you get the idea also another place to decorate for holidays if you like, make sure the mirror is not too dinky.

So I re-did my original layout so it is a more accurate picture. What makes this room tough to layout is having a short wall opposite a long wall. You really don’t want your furniture to extend beyond the short wall (if you can help it). I am showing a 86”L sofa opposite chairs that are 30”w x 40”d. I still think chairs are the way to go, but I also wanted to show sofas opposite each other so you can see the difference. Either one would work. Also keep in mind, I don’t know the actual length of the short wall. To further maintain an open feel, use furniture with legs or that are open on the bottom. Hope this helps!

Not a pro. Generally, I wouldn't use poufs in a TV room, which is how you're planning on using this room. Those are better in conversation spaces, IMO. No one wants to sit on a pouf and watch TV. Also your french doors open the other way, so you could encroach on that space with furniture a bit. Maybe even keep the door away from the TV locked closed. You're too far from the TV in all of these. If you have 1080p, recommended distance for a 70" TV is 9'. Everything else is closer. If you have 4K it's even closer than that (we have 4k 85" TV and we sit about 8 feet from ours). Of course you can sit farther away, but it just starts to feel like watching TV from across the room. I would reconsider a coffee table (sorry I know you said you want to keep it) and instead use the C shaped tables that can move/slide under a sofa for drinks etc. For additional TV seating you could do a sofa table bar with stools. Then you might have space in the back of the room to use as a small game area.