You can't go wrong with a 3-seat sofa and two chairs. The rug should slip under the front 1/3 of the sofa and extend past the ends of it by a foot or so. Don't buy another puffy leather sofa, but you can go traditional or contemporary. You might even consider a reversible chaise sofa (sometimes called a bi-sectiona;) They are easy to change up by switching the chaise from right to left. Make the TV your focal wall. You can divide living and dining by floating the sofa like a wall between them. Your two chairs would then go on the wall opposite the TV. Swivel chairs can help you arrange more ways too. I would switch the bistro set for a pedestal table and chairs to lessen the leggy look. Your lovely light is definitely meant for a larger table.

Thank you for your wonderful ideas! This is extremely helpful

Also, as for Large Empty Walls, think of this big space as three functional units (kitchen, DR, LR) and decorate accordingly. That is, I'd leave the TV zone mostly alone (maybe a tall plant in the corner, although of course a long piece of art over the couch), then hang a big cheerful poster in the DR zone, and then have a hutch or console table (with art over it) in the kitchen zone. Put your bench closer to the door, where you can put a basket for shoes (or whatever) under it.

In addition to adding furniture, keep in mind that things can move off the wall -- you might prefer the feel of the LR space if you put a narrow console table behind the couch, bringing it closer to the TV and also giving a spot for a table lamp, etc. Then you put an armchair in front of the window (maybe with an end table in the corner for drinks and another lamp) and another with its back to the dining area, a rug to unify it all, and that area feels functional for conversation as well as zoning out.

Good luck, and congrats on the new space.