We'll need more information and photos to help you. Where is the designated kids' play space? He looks old enough to play in his room. I'm thinking your TV needs to go on a credenza under the triple window at the end, flanked by the straight chairs and the large sofa should face the TV with its back to us. Is the other piece a chair or a loveseat? You'll need a large rug that slips under the front 1/3 of the sofas. You could add a coffee table for the large sofa and art over the mantel. Can't see where the outlets are for lamps, but you need some.

Hello! I have to agree on many points made in the above comment! It would be fantastic to see other view points in this room to better help you. Measurements would be extra helpful so we could link actual pieces! I would recommend that you change the focal point of the room to the wall we see here directly in front of us in the photo. This will maximize your space. This room has a lot of character with the woodwork all around so I think you have a lot of room to play with design! I would recommend keeping the fireplace visible and hanging a nice piece of art or painting or portrait above it. It will warm up this room and make it feel personal and like a lived in home. I would add a hanging light fixture in the middle as well to replace the lighting unit currently installed. You can get really creative with that! In fact, since everything else in the room is somewhat muted you could go with a very bold and unique fixture. That would be so cool! Would you want to keep the existing furniture and just move it around? If so, a behind the couch table could be nice for extra lighting. I wouldn't do end tables or a coffee table. I would go this route: large ottoman where all seating can share foot rest space and place a large and sturdy tray on top of it that would double as a coffee table when needed for the remote, drinks, a book or two. Some great throw pillows and a blanket can transform existing furniture! Pick a color and incorporate it. A rug is a must! It doesn't need to fill the room but it must cover the area in which your feet will rest. It will add coziness and homely touch. Maybe one that has a bit of shag? Just some of my thoughts. Good luck with your room change!

It would be good to see a picture taken from the far side of the room to get a better idea of the space you have to play with.

Keep the kid!

I agree that you need to get some vibrant colour in there, and I think it would be great if that could be done with occasional chairs. Don't choose bulky chairs, but do think of comfort. A neutral modern rug in an earthy texture would look great with a chair like this -- the shape is great with your sofas, too. Choose art to bring in more colour.

https://www.allmodern.com/Marled-Area-Rug-DAX3647.html

Painting from Saatchi Art

Yes to carpet. Keep your L shape but move then this way and off walls to begin.

Uttermost Nyala Ecru 5'x8' Rug · More Info

Seaspray 1 Light Table Lamp in Pearl White · More Info

Loloi Contemporary Jute Accent Pillow, Rust and Steel, 22"x22" · More Info

Add two ottomans like this in front of the fireplace, and put a fabric chair across from the sofa.

Studio 212 Interiors · More Info

Barcelona, you seem to have such a broad, generous heart. You "wow we love your room" all over Houzz. How about getting someone to write specific responses that reply to the actual situation, love or not? Post actual stock that suits the occasion, if you want to sell it.

Sorry, Madia, for hijacking your thread for a bit of hand slapping.

Manhattan, yeah, well. See above.

Beautiful living room. Love the dark wood floors. In my humble opinion a dwarf orange or mango tree in the back right corner would also really add some color and dimension to the space. Kids might find it neat too. Good luck!

That is a great space to be starting with! I also echo earlier comments - color :) Get some colorful rugs in their, Cushions on the sofas, TV seem's OK there but might be a bit high?

Could you hang a light / lampshade from the middle? Something cool and kid-like, like the Official Groovy Light's. Very cool and "groovy" :) Could add a bit of fun in there.

A toy chest and play mat would be a good consideration. Finally, framed artwork on the walls (think favorite movie characters etc). Good luck - great project to have!