Add a floor lamp in the corner and one on the end table. Will the rug be staying? If not, one with some navy blue would bring the colors together.

I like arc lamps behind sectionals in the corner so the light is actually over the coffee table or in your case the ottoman, an end table with a lamp fir the space in the first pic some different pillows with a bit more color a large piece of art on the wall behind the sofa.

Yes, rug will be staying. I love it and think the greys leave me open to quick change of color with pillows, curtains down the road. I do need another lamp or two and can't decide if should do floor lamp or sofa table behind sectional with lamp(s) on it. Although I do have ottoman tray, still squeamish about putting drinks on it, so like reaching back for a table...

End table in first pic is a cute little cart on wheels that I found at Home Goods. Love it but can't put lamp on it, and really not enough room for a wider end table. Debating mirror over sofa, or large art, or collage. Also need something for that corner! And maybe a window seat for front window...or a bench?

You have absolutely gorgeous molding around the windows. I would raise the drapery rod and extend it wider so you really notice the molding. Or get rid of drapes altogether (what I would do)

https://www.houzz.com/photos/query/large-window-molding/nqrwns/p/8

You're doing a great job! I love the suggestion of an arc lamp. That would bring the eye to another level, in a functional wall. The only thing I don't like about arc lamps is that they usually have a foot switch, which is kind of inconvenient. You need something on that wall. Don't muck it up with lots of little shelves and small pictures. Get creative--it's a long wall. My first thought is to paint a wide stripe (10?")of a soft coordinating color maybe 12" down from the ceiling. Now, in the space below that, think of an art installation idea that you would enjoy seeing. Once I installed a long piece of copper tubing (found at the hardware store in the plumbing section), using small brackets every 3-4.' From that copper tube, I hung black chain (although stainless cable would look great, too) at varying lengths. Using hooks, I hung large unframed artwork from those chains. It filled a long wall nicely, but did not look cluttered.

Lovely room! I agree with Patricia Colwell regarding a corner light. I would also pull the rug out a bit more from under the sectional. In the first photo, could you place the small grey console under the window? Another light source and one large piece of artwork above the sofa is all you really need.

https://www.greatbigcanvas.com/category/art-by-color/blue-wall-art/?shape=1&page=2

Thank you all. So many great ideas! Considering all and still working on it! Will post when complete! Thought my fourth pic had posted but looks like not. Fourth wall in room.