That really leaves you with the current arrangement, replacing the grey chair by the front window with kid stuff and leaving the floating living space opposite the TV. I'd really look into rerouting cable so the TV can be where the large art piece is. It's not usually very expensive and will be necessary in order to keep your walkway from running right in front of the tv.

A chair (or two) with an ottoman and a table would be great, especially if you are sometimes able to work while sitting in a chair with your coffee, tea (wine) on the table next to you. Is there any way to turn the desk so your back is not to the door and windows? That would bother me. It seems the shape of the desk fits the the way you have it but I wonder if you could turn and float it? If that worked then you also would be able to sit at the desk and talk with someone else in the new chair....I do see you don't have clients but I know my DH comes into my office and we chat. I don't work from home but bring work home and he sometimes comes in while I am finishing stuff up.

You really need to find a home for all the books unless you use them all , all the time. Right now that room is no where I would like to sleep. IMO cover the fireplace with the murphy bed in fact you can even get one that incorporates an office . IMO this could be an office and a guest room and forget the den idea, Ilove books but IMO most info can now be found online and in a small space actual bookcases take up too much room this murphy allows some book storage a desk for you to work on and nice place for guests to sleep . Honestly in this small space I think that is all I would do. Or a sleeper and a desk maybe use a closet for other storage guests really require very small closet space

remove desk from kitchen. regroup items /storage on that side wall. don't know what you plan as far as appliances /task areas.....but basically use that wall differently. Can opening into dining room be widened? could range be pushed over some...esp if oven is out of that corner??? I would utilize the dining room wall on the dining room side...even if it is reduced from 12-3 to 10 or 11 feet. reason being it is a straight shot from living room/great room it appears and the entertainment function including under counter fridge/some storage and counter would be great. Not ovens of course. You have a large dining room. I wouldn't reduce the size w those yellow wall configurations in the sketches but I would put some things into the space. You have entry directly from kitchen and just a few steps from living space [I think]. Maybe mock up your potential kitchen configurations in totality with the wall there. And besides maybe widening passage to dining room, don't rule out repositioning the opening to dining room...but get kitchen configuration options more delineated. Can't tell what you want to do within that area.