I think what is throwing it off is that it doesn't seem centered -- the table needs to be in front of the buffet (but then I'm not sure you have room for chairs! It would probably be easier to move the table and chairs in front of the buffet than to move the buffet (if it's like mine, it's full and heavy!) but you could see if that wasn't a better look and if so, then you could move the buffet itself.

Hard to tell from the angle of the photo, but can the table go any closer to the window? I'd center the table on the window, if possible, and fix the chairs so they are symmetrical - one toward each corner by the window and the other two placed symmetrically on this side of the table. How it is now, the chairs look wonkily placed.

Start by lowering your art. It should be eye level when sitting at the table. Put a tall fiddleleaf fig in the opposite corner.

what you have is a good start, it just needs some tweaks.

a sisal rug under the table, diff chairs w/some pattern on the seats, maybe lighter colors, and for sure a really nice lighting fixture over the table.

paint color, artwork (hung lower) and you could also string a rod just over the shutters and have drapes hanging on either side of the window.

In these pics, notice all the details...rug, lighting, table, chairs, colors, etc

see what you like.

see how the drapes hang off the sides of these shutters? like this. with a light, cool wall color

I like this table and chairs with the circular rug:

I agree with the suggestion to lower the art so it is at eye level when seated at the table. The top of the painting is currently above the top shelf on the opposite wall, and the sideboard pulls the visual weight of the items on that wall even lower. That's what most struck me as unbalanced.

I hate to be disagreeable, but with the complex corner ceiling treatment and the arch of your shutters, I don't think drapes have a place here. You don't have room for a rug either because it should be 36-42" larger than the table top, yet not run into walls or furniture on the walls. The issue of balance is the off-set of the table and buffet. The only way to solve that and keep it all visually in the dining area is to put the buffet in front of the window and pull the table 36-42" from it. Forget about your shelves for now; lower the art so it is centered 5' above the floor and then get out your sliders and change it up.

the drapes would be hung below the decorative molding