Could you try your couch under the window and leave the rug as is, as it should run horizonally vs veriically in front of a couch. Place you tv on the most appropriate side wall and I would suggest getting a low console so you can hide things and store toys. On the wall opposite, place you two chairs and you'll free up space near the dining room set. I don't think there is much more you can do in regards to placement, as your dining set is large. Accessory wise, I would get some drapes vs sheers (and don't tie back) and then add complimentary colored pillows that suite the drapes and your rug. Reconsider where you have placed your wall items as well.