Here is my first cut at your space. Rev. 1 (and btw, super-duper measurements!! kudos!). I put an approximately 11' length of sofa along the wall and since you have that short wall before the windows, I put a large ottoman type piece. I put a swivel chair in "corner" of the living space near the windows so you can swivel to converse or watch TV? maybe, or swivel toward windows for views. I put a 60" long (max. to maintain walking space to other part of the apartment) and keep it 16" deep because it will stick out 17-18 with baseboard, cords, etc. Set TV on that console. I put a 52 x 30 coffee table that would be 18" from the front edge of seating area. You could also put a small round decorative stool/table, beside the swivel chair for a place for someone to set a drink/cup of coffee, etc. Now to the dining area. To get a nominal seating for six in this area, you need a 30" wide table and you might have to have it made. A live edge custom table with metal base might be great in your space if that is a style you might like. Then in the living area, go modern and sleek. I would do the coffee table, even smaller if you wish with glass top and metal base to work with the dining elements you select. The chairs at the dining table have to be really narrow across the front seat edge. That is the big challenge. This table is 60" long and 30" wide. For every day, 4 chairs could be placed there, two on each side with the additional two chairs in the corners just to give a more open feel and help maintain views. You will need some additional lighting and a arc lamp would work well on the fireplace end of the sofa and you might want another floor lamp beside the window end of the TV console. Unless you shorten the sofa on the long wall, you have no space for end tables and lamps. So something to think about when shopping. I put a 36x16" bench in front of the fireplace for one person. The seating area will only seat 5 so total would be 6. You could bring in a chair from the dining set if needed and just squeeze folks in. Watch the size of cushions for any sectional you buy, each person needs at least 24" of space, and generally don't like sitting next to each other. Also, TIP, make sure your sectional pieces join together "under" the pieces so you don't have brackets on sides. This allows for greater flexibility in "next" house and even if you just want a seasonal change of some kind here. I'll play a bit more with this later today and see what other options I can come up with for you.

A couple of chairs and a table to make a small reading nookor better yet use that space for the DR and put a coat closet and a bench in the space where you now have the table because that space looks to small and is in the way of the entry.

Pull the sectional off the wall a few inches. Put a floor lamp in the corner at the chaise end. Put an end table at the other end with a lamp. Large piece of art over sectional. Look at bigcanvas.com or art,com for reasonable priced pieces. Put a colorful pillow on the sectional and pull the rig a little more towards the island so the leg doesn't look likes it falling off

Regarding the window that faces your neighbor, if you want to take advantage of the natural light you may want to get sheers. The size dining table will depend on how many people you usually have sitting there to eat. My dining table has a leaf in it, in case I need to expand it. I find that very helpful. A round table will be easier to get around than a square or rectangular one. An oval one may be even better. Depends on your needs. A chaise is very pretty, but I don't know how practical it is. I personally like more space to move around in than stuff. You have to consider the amount of space you have to work with. Try to make lighting an important part of your plan. I like a table lamp or wall sconce in each corner at chest height.