A simple tulip table looks like it would be right at home in your space.

I can't find a picture of it, but years ago when I was looking, I found this great pedastool table with what looked like a white and grey marble top . . . I still drool when I think about it.

I really like your sectional, are you sure you want to change it? It actually looks like your space might look more complete if you painted the strip above the windows in the same green as the entrance to the room. Also, that area that juts out makes sense as a focal wall since it doesn't conform to anything (actually, if you could put horizontal wood planks with a space between them on that wall, with an adjoing wood mantle, it would make that area look like a stunning focal wall).

What a great space. I really like this table in black, I think the area needs a little bulk and this one is shown with chairs that are similar to yours. http://www.homefurnituremart.com/homelegance-dining-room-set-dandelion.html

For the living room sofa, I would choose something similar to what you have now but in a lighter color, cream, beige. The contrast with the beautiful floor will be smashing. Add a new rug..just a little larger and very splashy with color, then use those colors for pillows on the sofa and for other accents in the area.

Love the chandelier, but it should be a little lower. Under the large piece of art are 3 great stools, I would replace them with one large upholstered bench with maybe a stripe or geometric fabric. The stools, I would move to the sides of the TV unit. Also place a large piece of art..maybe even a metal sculpture above the TV to give it height.

Lastly, put some color on all the wall surfaces AND the CEILING. No feature wall, the entire area should be the same. Look at this gray/green Sherman Williams Bonsai Tint - SW6436 http://www.sherwin-williams.com/homeowners/color/find-and-explore-colors/paint-colors-by-family/SW6436-bonsai-tint/ A little green on gloomy days is good.