Good ideas above, and I notice the pictures over the sofa are hung way too high. They would be better at about 6" over the top of the sofa. I would also address the mantel and find some mid-century glass or porcelain vases of the period and arrange a grouping up there along with a interesting lamp if there is an outlet up there. Looks kind of bare and lonesome right now. Could you put a wood box shelf under the TV to kind of ground the TV? It should be the length of the TV or a little longer. A low metal piece on the coffee table would finish off the overall look.

I would go with terrazzo since going with wood would be a poor design choice. I am not a fan of wall to wall carpet for a variety of reasons so that wouldn't be an option for me. Terrazzo is both true to the period and would look great with that style of the home. It is also more of an investment to future buyers as anyone who is looking for a classic MCM home is going to be thrilled to find terrazzo. However, wall to wall would no doubt be cozier but would need replacing fairly frequently

George, I like your idea of working floating shelves into the alcove. I had forgotten that we would have sides to anchor them, also. By the size of our TV, we should be able to put in 2 24" shelves on each side. That *might* be enough room for my items. Going to give it some thought. Disfromage, I did see that system from Ikea. I thought about staining the wood something closer to teak/walnut... Calidesign, I think my pictures make the room look MUCH bigger than it is! The windows really help with that! Our couch is only a love seat! Also, I am trying to get rid of these 80's Oak cabinets all over the house. I painted them in the kitchen and bathrooms, and just want to remove them here. Good idea to change out the ceiling fan, though! We moved the Credenza into the house as we start demolition. I think it is going to be very pretty in the space!

Sounds like a fireplace re-do might be a longer-term fix. In the meantime, I'd paint the mantle a dark brown, a similar colour to your end tables. It's not trim and shouldn't be white. It pops out too much in the white colour. Another idea that doesn't involve any ripping-out is to go right over the existing mantle using a mantle slipcover in wood. Here's one of many how-to's on the internet. If you stained your brick as well, you could have a whole new look. https://www.fwmadebycarli.com/2011/01/making-of-slip-covered-mantel.html