Agree with painting the walls and definitely the trim. That will all help immensely. I would also recommend getting a sectional with a chaise and getting rid of the 2 seater sofa and singular chairs. That will warm it up and get rid of all the dead space you have on the left. In case you want to do a little bit more I would change out the fan for something more clean and modern and look into window treatments for those large windows.

I agree to painting the bookcase.

SW Alabaster is a great warm white for the walls and ceiling, I too would paint the trim the same, different sheen. blueish ok, stay away from gray. Why not the same color as the walls? Different Sheen, same as trim.

Mount the TV on the Left built in. Remove the light kit from the ceiling fan.

a larger area rug so the furniture can sit ON the rug.Make the Rug the color statement (you have great natural light, you could go pretty bold) Drapery panels on the windows/doors. rod at the ceiling and extended beyond the opening to soften the space and improve acoustics.

Suggest soft white walls/trim, but dark bookcases to create warmth/to better complement the furniture, and a rug will pull it all together. I feel your fireplace needs updating if you want a more modern feel. Perhaps others can help, as the only thing I can think of is removing the side panels and painting everything (maybe mantle could remain as is).

I'm being a contrarian here, but leave the wood and fireplace alone for now. Both hamonize beautifully with your gorgeous floors. Have a cabinet finisher remove shelves on left side and put your TV there as Patricia suggests.

Sorry, but the current sofa and chairs, and rug, send a 1980's frat vibe to what could be a stunning transitional room. Furniture and rug should be changed, not the fixtures of the room, IMO.

Consider getting a warm, camel/butterscotch sectional, one side to face TV, the other to face the outdoors. Get a around modern coffee table and a much larger interesting rug in warm colors.

Note the warm colors here that echo floors, wood cabinets, fireplace. This room reminds me of yours--the built-ins, the fireplace, the wood trim.

New Waterfront Home · More Info

Rustic Organic Reclaimed Wood Coffee Table, Natural · More Info

Paint the walls a warm white that brings out the wood. Get some great modern art to put above the fireplace. This palette in a modern abstract would instantly modernize your room. It picks up camel, warm wood tones, stone finishes from fireplace.

HORSEHEAD Contemporary Fine Art Gallery Wrapped on Giclee Canvas, 40"x40" · More Info

Rug in modern pattern with camel for future camel sofa:

Aqua Fusion Rug, 6'x9' · More Info

Amer Manhattan Orange-Navy Abstract Rectangular Area Rug 7'9"x11' MAN417911 · More Info

In the above photo, walls are a warm off-white. Note wood trim above doorways. You don't need to paint the trim right now.

White wall paints that go with wood trim:

https://www.houzz.com/magazine/11-terrific-paint-color-matches-for-wood-details-stsetivw-vs~9025200

IMO the rug is all wrong for this room. The place is beginning to look like an igloo. Too much white and not enough contrast.

I think it would be better if all seating could actually see the TV, so I'd change the seating positions.

IMO remove the fireplace mantel and apply tile OR paint that fireplace wall to give it a modern feel. Keeping the bookcases and painting them the bluish grey would work really well with the white of the trims & bring together the room. I would also add a feature light/fan.

It looks like painting the walls and the built-ins might really help you in modernizing this space. Please take a moment to look at the images below for more ideas on how to modernize your space.

Built-ins and rug idea:

California Ranch Transformation · More Info

Fireplace ideas:

California Ranch Transformation · More Info

Charming Cottage: Living Room · More Info