I think panels on a nice rod, hung high would look nice. Not too dark a color though. Good luck! :)

You have a lovely well balanced room. My first choice would be for Roman blinds because there is not much space on the walls for curtains to hang when they are open, and they would therefore block too much light. If however you decide on curtains, keep them light colored and hang them two inches from the ceiling to create balance with the ceiling to floor fireplace. Your favorite warm colors can be used for accents - e.g. artwork, throw cushions, (minimal number of) ornaments etc.