Are you keeping the existing leather arm chair or replacing it? That cognac color looks great with teal, but another chair seems like it would be too much. Perhaps you can add cognac/camel throw pillows (no more than three) to sofa. Disclosures: My own LR has a teal/camel/ivory color scheme, so I’m a bit biased.

The teal sofa and chair by window are cool colours. The leather chair is warm. If you are adding a 3rd chair---go for a warm colour to balance the seating.

What are you going to do with the 'flesh-colored' fireplace. It's just not the right color for the room.

If you're feeling artistic you can do a custom paint job on the tiles.