Different view

Another view

On a first review, the carpet is pretty but too small for that dining room set.

The right curtains would make a world of difference, they can be either heavy or light but much be rich in detail.

A chandelier could also have a great impact.

Consider, if this work for you, removing two of the chairs from the table and putting them against the wall on either side of the windows, that way your table can be better appreciated.

The scale of the potted palm and the dark disk on the wall do not do much for the room. Two large potted palms or ferns on large glazed pots on either side of the fireplace would look great. The print atop the FP is the wrong scale for those sconces. Consider putting there a tall or narrow painting or antique mirror.

Straighten out the small buffet and the bench, or remove them altogether. Do not be afraid of empty spaces.

Thank you ! Great ideas. What would you put on wall where clock is ?

Long linen drapes ?

curtains would make the space more homey, and will make a big difference! also maybe add some different (colorful) accessories on the table that don't blend in, and will accent the table better

You have a lot of the same tone wood in your furnishings, floor and woodwork. Have you thought of replacing your dining chairs for upholstered chairs in a beautiful fabric? It will break up the monotony of all wood. Linen drapes will add softness and a different rug to soften and brighten the space.A beautiful, custom,sisal carpet bordered in linen to replace your dark, carpet you have now. The whole space feels like it could be brightened and lightened with color, fabrics and textures.
Don't buy anymore wood furniture. Try other materials such as glass, metals for a little sparkle. A beautiful light fixture would add some sparkle and interest.

Also the things hanging on the walls are way too small. It you are going to do a sconce, make sure it is much larger in scale. Again, I would not choose brown for my accessories, choose a color you love such as aqua, tangerine, yellow

wainscot on walls and wallpaper on top or foe-paint

Here is what I would do.
Paint the table a hip color of medium blue-gray. Distress it.
Buy all new chairs in fabric in a light color.
Do light drapes in same light tones.
Add height to plants. Place on metal stand or table.
Add bigger scale art and color on walls or a table runner.
Add a great chandelier; big.
Use a light colored sisal rug with a color border.

I think your home is wonderful!
I agree with adding larger brighter art over the fireplace, and perhaps more color via art on the walls. I think your sconces are fine, they just look kind of lonely right now. A taller ficus or Palm might not hurt.
Another option to consider, given you have a sort of traditional American dining room with a clean slate of white walls, might be to start a collection and show it off.
Perhaps majolica plates, or Mexican talavera...or perhaps textile handcrafts, either Native American or cleanly geometric Amish quilts...