I would do everything to the room first and then think about window treatments. The clean no curtain window could work here especially if privacy is not a concern. The side chairs would be nice upholstered in an accent color to add warmth and softness. The mantel is a bit low so I would fill the wall mantel top to ceiling with a mirror or large painting...leave the sofa as is, they are nice I think and add pillows in your accent colors.... Toile chairs would be fun! Example of large mirror and large greenery over the mantel

That Karastan rug creates a giant hole in the center of your room and I would relocate it to a better location. Gold lamps will pick up the gold in your framed tapestry and drapes will add texture to your room. Put the valet in the walk in closet.

First cjange all those bulbs to LED 4000K and if some are Edison bulbs replace those with non Edison LEDs . Then IMO a color would be nice for the stools . I also like swivel stools especially on wood floors

I like the shutters. I am not sure why but I kind of feeling resistant to putting a lot if fabric in there - drapes and sheers would be a lot of fabric as 6 long windows. I like the outside coming in as it is somewhat pretty in back yard - wooded, etc. The light fixture is a ceiling fan. Not sure my hubby would be okay with not having a ceiling fan in there. I do not care - however I do like the style of the fan, so I am not opposed to it. I don't like the style of the chairs, to be honest. They are also chipping and they are so hard/annoying to clean in between the spindles, imo. One of the chairs has a broken spindle now; although, my sil boyfriend says it's no problem to fix (he's a woodworker). But I agree - it's so hard to get furniture that does not fall apart. It's the reason I still have not replaced the dining room set my mil gave me even though I don't like the style much (although I have modified it enough that it is growing on me ), it wears like iron! My boys would have destroyed any other set in there long ago. My mil's set is like it's indestructible, I am not kidding. I Know these are super great quality because I have them as counter seats in my kitchen at my island and they are quality and wear like iron: But they are very pricey. I would love suggestions of runners and rugs! Also since the light fixture/fan is round should I think about replacing the table with a round one?