So far, it is all very neutral. What color do you want to add or will you stay with neutrals? Do you have a particular style that you like? The one inspiration picture you have saved in your ideabook is do-able in this space if you want to go that direction.

I would add long cream colored drapes on the black rods you have. More sheer if you don't need the privacy. I would look for a large piece of art for the non-window wall.

Pick the art first if you can,. Drapes and rugs are easier to find.

Art is neutral IMHO. There's no way art can clash with anything in your space. So go with art that appeals to you. In my former home I had a calendar with copies of famous Japanese prints illustrating each month. I loved the calendar art so when the year was over, I got some plain black frames at a home store and created a six image picture display for my wall, much like the one in your inspiration photo. That's one approach for creating something like that. The photos can be of anything that catches your eye, even arty photos of your family if they're not full on faces staring directly at the diners! My current dining room has some huge framed watercolors of the beach that I got for a pretty low price at a local art gallery. The framing was what was expensive. I like those because they bring my favorite outdoor scenes indoors. That's another approach to art, using landscapes or nature scenes or botanical prints to bring the outdoors in. But if you're a music lover, you could also decorate with album covers or concert posters. Or if you love physics, pictures of the planets. Or maybe you miss color and just want some non-representational art that has beautiful color combinations. Or maybe you have some heirloom china that you would maybe never use but would look great hung on the wall. The point is to find something that you are going to enjoy in the room. At this point you have a blank slate. Once you know what appeals to you, then you can begin to collect pieces that go together.

See how easy. :-)

I also love the neatly spaced botanical or architectural prints or b/w family photos.

The great thing about using relatively cheap prints in a picture montage is you can easily swap them out if you find something you like more. You can always get something more expensive, but all of the things you like for a montage would be easy to do. Just google any of them and also maybe look on Etsy. You'll probably find so many it will be hard to pick from! For inexpensive prints, you can't beat wall calendars! For example: https://www.amazon.com/Calendar-Fruits-Garden-Vintage-Pocket/dp/B071J31YLT/ref=sr_1_fkmr0_1?keywords=seed+packet+calendar&qid=1550942305&s=gateway&sr=8-1-fkmr0

Wanna send my your chandelier?! ;) (Joking but I have been looking for a similar one to replace my current one, came with the house and is brass with glass tulip shaped globes and fake brass leaves and looks a bit like "Audrey" from Little Shop of Horrors.) Your chandelier is classic and looks really nice, I wouldn't replace it. I'd spend my time and money getting the other elements of the look you want. Like rug, curtains, art, maybe some fake or real foliage, table linens and centerpiece.

Edited to add that I have a mirror on the wall in our dining room and we don't like it. Diners don't like to sit and see their reflections, AT ALL. YMMV as far as how you would place the mirrors. I am currently contemplating removing a console that makes it tight in there and replacing it with shelves, so I think that would be a great idea, but I would be sure they have lips or bars or something to keep things from being accidentally knocked off. Again, YMMV, we are clumsy. Google "shelves in dining room" and you will find some awesome inspirations. The style in this link would look great with the seed prints, if that's your vibe. You might want something more sophisticated. Depends on whether you want to steer in the "modern" or "farmhouse" direction. https://www.thewoodgraincottage.com/2017/02/17/moody-dining-room-shelves/

I just realized that this pretty room is part of the “3-butt” sectional home. I just love your home and the finishes. What other unused decor do you have that might be used in this room?

Some inspiration from Ballard Designs

Have you considered wainscoting? I think extending it down from the white line across the room would look really nice and brighten up the room

Don't love the windowpane mirrors. The chandelier is cool as heck. You could inject a little character into the room with chandelier bulb shades. Maybe that's where you go for the b&w check you like. Why don't you wainscot the wall up to the chair rail? Panelled wainscotting, not bead board. I do think you need to add some color and texture. It's all a little chilly.

large print. a gallery wall is very hard to get right but if you think you can, go for it!

Finally found the dining room shelves picture I saved for inspiration. Reminded me of your style.

^^That's really really cute...

Did you know you can buy paintable beadboard wallpaper? So simple to diy...

Agree about the mirrors not working--they would compete with the windows...

those are beautiful! Love them in your space

As for the chandelier, with something that classic, there are ways to bling it up with beads or fake foliage, or put shades or decorate the sconces on the bulbs, to change the look without totally changing out the fixture. That's what I love about that style.

I would go curtains like this and bright colored art, similar to this

Did you look in wayfair? They have them

https://www.wayfair.com/decor-pillows/pdp/august-grove-northridge-plaid-room-darkening-rod-pocket-single-curtain-panel-w001367510.html

Don't you mean yay or neigh! ;) I like the picture.

BWAAAAA HAAAA HAAAA!!!!

I like the picture too...but don't you want a bit of color?

I love the curtains! The picture I like but I’d rather see brighter colors

Like this (world market)