For me I would re arrange the furniture, is the chaise fixed, could you run it across the room with the TV and unit on the back wall, a couple of lamps. The armchair fit in between the TV and the sofa? or just the foot stool and then the armchair used separately as a reading area with small side table, both placed in front and to the right side of the window, without seeing that part its hard to know
Your room has great neutral colours but is very rectangular, try adding some rounded shapes in there like vases, mirrors, cushions or an irregular shape rug (like a cow hide rug) to add interest. Also the TV so close to the dark cabinet looks a little heavy in that space, can you detach your TV from the cabinet and wall mount it a little higher up? Then you can put some plants or eye-catching collections/ornaments on the top of the tv units as well.
We agree with the commenters above - that wall is perfect for some amazing art! The little hints of mustard and mid century details that you've already incorporated would pair great with a graphic rug - a few suggestions: