Just move the furniture away from the walls and closer together around the fireplace.

Although I don't like to walk into the back of a sofa, I think yours would work well facing the fireplace. It will function better for watching tv also. You can then place a chair on either side of the sofa facing in. In this case, symmetry will work for you so I would prefer two pieces that match in colour and scale if not also in style. t will be quite cozy to face the fireplace wall.

An open piece of furniture like a rocking chair or other kind of unupholstered chair would be nice. No more pillows. You can find some very interesting old ones at antique shops or flea markets. Can you get a lighter looking table, like glass, to lighten things up? How would it look if you turned the sofa at a right angle so it faces the fireplace/ Yes, you would be looking at the back of the sofa as you walk into the room, but the room looks long enough for that. That's a nice leather chair and might balance the room better if it were in the corner where the small chair is now. Then I'd put the little table next to the sofa like an end table. Your rocking chair or whtever you find should be light enough so you can move it up next to the fireplace or into the corner. You need something green in there; everything is brown/red. Maybe just a nice big pot of ivy on the mantle. There is a pot of ivy in the White House that has a long story attached to it. It is frequently in pictures in the oval office. If you watch, its size changes over the years, but it is the same ivy. I think it is like 40 years old.

Do you really use all of the seats? Do you really need the small chair replaced? Have you thought of putting the tv above the fireplace or on the wall the couch is in? It looks uncomfortable to watch the tv from the couch. Maybe you could angle the couch and chair kind of like a v in front of the fireplace. I think I would consider getting an ottoman or a small round coffee table and elk mating one of the chairs.

Elk mating.....lol I meant eliminating.

A photo from another perspective would be helpful. Mounting the TV over the fireplace would make it visible from all seats. This is exactly like so many homes in this area (my mom's house included). Your placement is the best that we have seen (based on your photo). I would suggest editing some of the accessories in your bookshelves and around the room to keep it from appearing too busy.
Keep us posted.

I love the v suggestion! At first read, I wasn't sure. I tried it and really like it. I agree on the green ivy, too! Great ideas by all!

The room would look much better with a bit of editing. To much stuff for that size room.

Vanessa's idea is good from a good look point of view. It is not the best for TV viewing. By the way the room looks now that seems important to you. If you put the TV that high you will not be able to use the light on the fan 9not a big deal). The TV would need to be tilted downward. The chairs would be useless for TV viewing. I agree with her on getting rid of the mirror and remove the clutter. Move the leather chair next to the sofa. this will change the flow into the room but it will look better.

Start the new year with a clean slate. Get some boxes and pretend you're staging your home for sale. Clean out everything that is loose (rugs, pillows, books, accessories) and box items by "I don't need this," "warm season" decor and "cool season" decor. Store the box that is currently out of season, and take the "don't need" box to Good Will or such. With the mirror down, work with TV connections and install it there. Place your sofa this side of the fan facing the FP. Angle the large chair to the right or left facing the FP. Replace the small chair with two swivel chairs opposite the large leather chair. Try the mirror in your dining room. Get a larger area rug - you want the front feet of the sofa and two swivel chairs on it. You might try an indoor/outdoor rug. You can get pretty large ones at homedecorators.com for little money. That way you might afford two of them (warm season and cool season) to change out twice a year. Take the tutorial here on Houzz about arranging shelves and put back all the current season accessories using your new decorating principles. Pillows to coordinate with the rug, and for warm season, a cream slipcover for the sofa would complete the makeover.