Initial thoughts are…I’d leave the fireplace/mantel as is…the mirror frame echoes the warm browns but adds a different texture and is lovely with them. I think I would remove the blinds if privacy is not an issue; better to bring more light into the space and to open up the room…feels a bit like the height is overpowering. If there is room, I’d float the sectional a bit so it is not right against the large window. If possible, I’d lower the chandelier so it’s reflected in the mirror. Then either fill all of the shelves with books or curate them with interesting, large scale items with different shapes textures, and materials…hopefully, some warm metallics, textured organic pieces, and meaningful collections. Then a few pillows in complementary colors/textures

I would do something with that huge TV in a small space. Your room is very beautiful, but it needs color on the walls, curtains on the windows, art on the walls, and books on the shelves.