That tufted slipper chair is very formal/feminine (think bedroom or dressing room where you put on your shoes.) The other two chairs are outdoor style wicker, so they won't work either. Do you have a covered porch or sunroom for them? Get a different rug - much larger. It should slip under the front 1/3 - 1/2 of the sofa and extend past the ends of it by a foot or more. New chairs should echo the chunky/masculine feel of the sofa. You could go with navy but it should be echoed in the rug colors. The items hung on the walls are too high. Centered at 5' above the floor or 5" above a piece of furniture works better.

Thank you!
The blue chairs will be moved outside.
Do you think we should keep the 2 raws of seats or arrange all near the couch?

What does the couch face? Fireplace or TV? If not TV, then move it back to the wall and lower that art piece to 5" above it. Then two chairs can "L" with it, facing the window. If you have TV in front of the sofa, the two chairs should be swivels so they can turn to watch. If you need the couch closer to TV, then a sofa table behind it might help. You could put the hassock under the sofa table to pull out for extra seating. More pix of all your walls would improve possible suggestions.

Thank you for suggestions!
Here are more pictures. The ceiling goes up to the 2nd floor. This room is between the floors.
We are planning to replace the TV shelf with sth else as well

Nice big space. You have room for more furniture and can make the room complete if you add casegoods too. I suggest you consider layering the hide rugs over a large fiber rug. Yours are a bit small. Try them either side of the master bed and get a larger one for the living room if you like the hide look.

Center the TV on a credenza about the size of the cubbies under it now. Here is a chart for distancing the seating from it.

Here's a good arrangement for a room as large as yours. Just use 4 swivel chairs and a coffee table. The fiber rug should hold all the seating, the hide can go in the middle and get a glass topped table so the hide will show through.

Do some measuring and taping out with painter's tape to see what size will work with your sofa and room size. Your walls appear pink on my monitor. I think once all the upholstery an rugs are in place, you should think about changing that. Paint is the last item in a makeover project because it can be custom blended to work with the fabrics and upholstery.

Thank you very much for the ideas!

In addition to other comments, your wall color is what's throwing it all off for me. Not sure if it's just the photo but it looks like it has a pinkish tinge to it, and that doesn't really go well with the yellow/beige and blue.

Have you placed the piano anywhere else? like behind the sofa....

could a chair go where it is currently... even lighter one to be moved in front of tv...

Piano should go agains the wall as it is an electronic one and needs to be close to an outlet.
It can possibly go where the nave chair now are

If piano stays there would not be enough space for a chair since there should be a bit of free space behind it. If the couch gets to be pushed back, there might be space for a chair

People do all sorts of things - try a 'work table' behind the sofa... see gallery wall too.

Wordly in Los Altos · More Info

Blue chairs are faux

Here's how I would lay out the room...

Agree with @er612. Once upon a time I had a piano and that was where I put it. Perfect spot for it.

I would move the gray chair to another room and the piano to where the navy chairs are now. I like the navy chairs and and would arrange near the sofa.

Using headphones a player could be 'away from' distractions and play sort of alone on opposite wall.

this is a unique house, but not so unusual -- here's a natural chair, all mixed in. :)

The pics below include 8x10' and 5x8' rugs. The ottoman is next to the TV for additional seating when needed but this will allow you to get a larger coffee table. You could also put the ottoman behind the sofa under a sofa table.

Thank you all! Very good ideas!

too bad if there's no outlet around the other wall. Get one put in!?

There is one where navy chairs are, so should be all good!

So, piano can be tried where blue chairs currently are?

Yes, can be tried there

Here's an idea if you like the sofa an 4 swivel chairs concept. This rug is gold and navy and comes in 31 sizes. You'll want it large enough for the swivel mechanisms to be entirely on it. The sofa can sit on it or 1/3 - 1/2 on it.

Have not touched the piano yet, but moved around some furniture to get an idea

I think the piano is fine where you have it. Once you place the sofa and chairs at the correct distance for viewing TV, any additional space behind the sofa can be used for a small game table and chairs. If you serve alcohol to guests, you could put a bar on that wall. I think the best move you can make right now is to eliminate the rugs and arrange the furniture so it isn't crowded. Looks like all the seats are almost touching; I would spread them apart a bit.

Geometric modern rug, and strong shapes in gear item.

On the other hand, there's a kind of softness in natural hide.... and sheen in curtains in an opposite style -- almost.

In open area, personally, other combinations would complement each other better.

If piano and rug stay there --

hang something between the 2 blue chairs....? I'm not expert, but maybe a soft geometric could complement his rug, etc...

Silver Waved II Tin Mirror · More Info

W 25" / D 2" / H 34"

This natural view seemed to have blue [sort of chair color] and darkness of media area, and might be ok direction. [I don't see it with the geometric rug]

"Mono Lake Sunrise" Wrapped Canvas Art Print, 60"x40"x1.5" · More Info

Sorry, instead of your rugs, this type? with distressed-natural like wickery, and white like curtains. I don't think it "competes."

Tribute Eisley Rustic Distressed Transitional Diamond Lattice 8x10 Area Rug by M · More Info

Your last photo of moved furniture and geometric rug behind sofa -- this larger simpler rug with seating arrangement?

Momeni GRAMERCY GM15 BLUE RUG · More Info

I also like this option --- best of 'luck' to you .. :)

Safavieh Monaco Mnc225E Rug, Grey/Light Blue, 8'0" X 10'0" · More Info

I found a throw with green in it - funny that the green plants in your photo jumped out at me.... could add some green.

but this throw adds a femininity onto white curtains, etc....

FauxMohair Shabby Chic Throw Blanket, 50"x60", Aqua · More Info

Thank you!

You're welcome! Are you the pianist?

Just like to play for myself and the family . Studied for 7 years 20 years ago.

That rug you have in front of the couch would look better with the piano and that count should go in front of the window or cross from the window

Yes.... so they sit at sofa and chair and sing ? it's a great activity to draw people together.....

They just sit, no singing yet))

Above was a green idea for a throw. I typed wrong - not that soft sweet aqua which was nice. But a green you choose could be same depth that the blue is, medium...