Here are pics of some more walls. The second picture shows the entrance to the living, dining on the left

Adding a primary color to these spaces would help 'warm' up a bit.

I'd put a large rug in the living area to warm it up. I would also paint one or two of the walls a darker/warmer color since it's such a big white space.

Check out my artwork for those walls. I have many originals, and many large art panels printed on canvas. I can ship in a tube.

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Enjoy decorating!

One more suggestion is to put the sofa in front of the window, but pulled out a bit. Put the tv on the wall where the art piece is now and put that art on the wall in the dining room. Get a side table with a lamp for the sofa and a nice big rug to put under the sofa and coffee table. Think about adding a chair with a pattern in it to the room.

OR slide the tv down to the corner on the wall it is on now and angle it there with the wall and the window. Then flip the sofa so it is also at an angle, facing the tv....floating in the room.

Your room is big and void of color. Yes there is too much brown. If not replacing. Add light colored pillows big in a cream print. Add teal to mix. Get a 8 x10 area rug. Go cream base and a contemporary design in very bold colors, red, yellow and black, teals mix it up. Can you get regular chairs. Those look like game chairs, can they go in kids room? Pull sectional into room out of corner face TV wall. With big rug and a 36" ottoman square. In a color. Maybe zebra for fun. On TV wall. Get a wall to wall floor to ceiling or close to it wall unit. Ikea has some go white. Get. Long low media cabinet. Also Ikea in white. Place TV on top. Fill wall unit with colorful pots candles books. Just don't over do leave 50% empty. You could paint that wall a darker (2) shade of walls. After you have centered sofa in room more. On wall behind a very large art contemporary 40x40 hang very low. On empty wall in dining area. Get a long 6-7 ft chest. Something different. Asian feel red lacquered would be fun. Over it add big art piece bold colors 40 x40 hang 6" above top of cabinet. More art big by dining table. I would change chairs to a high back leather in Teal. Pier one has them. Your whole place needs color. Area rug under table 8 x10. Solid teal. Add big palms in corner to fill and warm up space. In chairs get two swivel barrel type in a print. Modern go taupe and blue/greens. Wi Dow panels on ends only in teal. Ck bed n bath. TJMax a good source. For art ect.

Light over dining table I would change to big drum style in a black or silver shade. Hang 36" from top of table yours is too high.

Get another centerpiece just go 5 candlesticks in different heights. Group together in center, go white, silver and black. White candles. Ikea good price. Place a palm in corner behind sofa. Add a floor lamp in stainless too.

Remove all things from window ledge.

Place pic over sofa on dining rm wall. It's to small for that wall.go twice as big.

In ceiling hang a chandleer drop to 7 ft from floor. A big drum style, like dining room or a round one with brush nickel.go on line. Make it different.

Looks like you need privacy on windows. Instead of ends only get a traverse rod so you can open and close drapes. Cover entire window wall area. Make them full. To the floor.

To be cost effective just put loads of plants and some brass planters . This takes care of floor and walls . Curtains will brighten it up and near the door a long runner carpet.