Is your house a split level and the ledge can be seen from the foyer level? If it is and it were me, I put together a grouping of portraits and family photos organized in various sized frames.

Here goes Bronwynsmom again with the mirrors!

But I think you can work with the awkward space by hanging a large - really large - square mirror, in either a good wooden frame in the tones of your tile floor, or a dulled down gilt frame, on that back wall. In that space, it would open the wall and read like a big window.

Then I would find one tall, striking vase or ewer in a very pale color, and fill it with something dramatic like big feathery plumes, and put it on the ledge at the front.

Alternatively, a tall slender tree in a stone (or fiberglas...some of the new ones are really good) pot, if you have some natural light for it.

And nothing more. A space that starts out awkward can be strong and dramatic if you don't fight it, and keep the statements bold.

Here's a plant - it would have to clear your heads as you go by, of course...and a bunch of other examples of tall vases and pots, depending on your taste and style.

A vote for a very tall dark vase for the first corner (the one on the left in the photo) and a matching shorter vase
in the right hand corner.

Perhaps this grid of artworks on the large wall?

If possible - add some very small uplights.

Here is a link that might be useful: grandin road -- four metal artworks

It's an interesting space -- I like your curved stairwell, and how the shape of your light fixtures complete the curve. The white trim on the right hand soffit (if that's the term) doesn't seem right though. Hard to tell without photos of surrounding space, but I think it would be better without the trim. I like mirror/plant option, but another thought would be a large mobile -- at least if your home is contemporary.

Here is a link that might be useful: mobiles

Lukkiirish, yes I suppose you would say it's a bilevel. The main entrance is 3 steps down from the living room... You can see the steps on the left of the second picture. Down the curved staircase, which you can see straight ahead in the first pic, is the basement. The first picture is the view directly coming in the front doors.
Bronwynsmom, I adore mirrors and have seen so many that I love. My only hesitation is that there are double mirrored closet doors in this space (you can just see them in the right of the second pic). I just wonder if another mirror would be overkill?
I do like the idea of going bold on the large back wall... Perhaps a large piece of art? And I definitely need to put something large-ish on the smaller ledge, as whenever I've left it empty, it's become a drop zone for my kids various junk :/
There is up lighting above the area on the right of the first pic, and above the closet. The light fixture is a hanging fixture, so I'm thinking a mobile probably wouldn't work.
Fwiw, I would probably describe my style as transitional. I plan to stain the maple hand rail etc, when we replace the floors with a darker hardwood.
Thanks so much for the ideas!

I would put a large vase on the square part near the front and put a large piece of art on the back wall and ignore the curved ledge.

I am with Annie D and others - If it were me, I would put a simple crisp large scale white vase on the front square (prob from West Elm or Wisteria), and a nicely framed piece on the back wall. I think it would seem purposeful but not crowded.

If you do like the idea of a mirror, I don't think the existence of the mirrored doors is a problem. Since it isn't really in the same space, it will seem more like an opening in the wall than like a mirror.

Whatever you choose, I think the consensus is to keep it big, bold, simple, and uncluttered.

Post pictures of whatever you decide. We'd love to see your solution!

What is everyone thinking in terms of orientation for the art? My habit is to go for landscape, but now I'm wondering if big BIG portrait might be the way to go. Something that fills up virtually the entire wall? Possibly an abstract of some sort....
Thanks again, all!

Big. As big as you can. With a bold image and a lot of white space, or a dedicated light, because you are never going to see it very close up, and the wall is a bit shadowy now. You might, if you like, consider a reproduction of a great poster...here are a couple of ideas, if they appeal to you:

I can see a large square piece of art or something taller than wide....but not wider than tall.

oh I saw a perfect vase at Home goods for this! Do you have any of those stores near you?

I'm up in Canada but we do have HomeSense which is just our version of Home Goods. Hopefully I can make it there this week at some point. I'll keep you posted if I find something that might work! Thanks!

I agree with mjlb about the white trim on the right side, that's the first place the eye goes. An idea is to paint the white trim on the right side the same colour as the wall, so it doesn't jump out at you. And yes, then go for the large art on one side (the larger space) and then step back and see what else it needs.....