I would remove the bulky white bookcases and place the TV there. It should hang at seated eye level above or on a credenza 25% wider than the TV. Instead of a sectional use a chaise sofa, often called a flex or bi-sectional. They have a movable chaise portion you can switch from right to left when you want to rearrange. Angle the brown/blue chair to the right of the FP out in front of the slider and place the sofa so the back corner of the side with the chaise portion aligns with your opposing angled door and the FP. Use a sofa table behind it. By the window you can set up a pair of chairs and a small game table for the two of you to enjoy chess, checkers, Scrabble, UNO, poker, etc. Nice spot to entertain if you'd like a bigger table and four chairs. Center that hutch on the wall and use it to store board games, playing cards, poker chips, etc. I think the wainscoting from the hall needs to come on into the living room rather than just stopping dead and causing another visual "divide" to the room. Paint the beam to match the ceiling and it will fade away somewhat. Matching curtains all the way around. New, lighter bar stools, a piece of art above the mantel. Keep it within the footprint of the firebox below and keep the mantel clear of lots of little items. Just add a pair of chunky candlesticks on the right side.