will this be a sitting room or a tv room or a formal room?

the piano looks a bit out of place. need to pull in some more browns if you plan to keep it in here. a larger coffee table might do the trick perhaps an end table. table and floor lamps. every thing is very pastel. consider maybe a punch of dark blue or a bold gray pillow. a sheep skin throw (faux) for the bench on the piano. and maybe one large vase with tall flowers on the top of the piano, but im thinking nothing at all.

The piano should not be put at an angle, it just looks wrong. And it should also be on an inside wall, so that cold temperatures don't affect the tuning and sounding board.

my impression is your furniture is being shy, it needs to come in from the walls to join the party. agree on pianos on an outside wall, that is last resort only (and never for a good good piano).

I would move the round table closer to the sofa & place a magazine to one side of it. Also add a small shallow bowl on it. Move the ottoman in front of the other seating. Move the large plant over in front of the window where the ottoman had been. Place a small console table in the entry foyer & place the vase of flowers to one side on it with a vertical mirror above the table and a small tray on the other side for keys.

You will need some small end tables for table lamps in the living room. Placing the piano near the window is not the best place for it due to the sun. If you can find a better place for it away from the sun would be best. You did not provide a photo of the wall opposite the sofa wall. Can you do that for us to better help you?

Center the piano on the sofa wall if you don't have an interior wall where it will sit in better health. Make it the focal point and hang the two pieces of art above it - try them side by side or vertically with only 3" between them. Then float your sofa in the center of the room, facing the piano and "L" the loveseat on the window side of the sofa so that it faces the foyer. Now tweak them so they are centered on the opening to the foyer. Pull the round table 18" from the large sofa. Take the hassock over by the piano and angle it floating on one side of it as though someone could go and sit and listen to the music. Place an upholstered bench and the plant at the window. Add a sofa table behind the big sofa. You can put a table between the two sofas. It should come to within 1" of the sofa arms. Add your powdery blue/gray pillow color to the room by painting the backs of the display cabinets that color. Let's see a pic of the end of the room opposite the sofa, so we can tackle that. Once all is in place, we can work on the right area rug to anchor your floating seating.

Couch under window and love seat facing. Add your glass table next to couch and add a lamp. Piano on long wall with only a few silver frames on top and with your art above. Add a much large coffee table and you could place the ottoman in far right corner near bookcase with a floor lamp.

Thank you all for the feedback!! Some of you said to place the couch facing the long wall and place the piano on the long wall, we thought about that option and it wouldn't work because we will have a wood fireplace right in back of the couch and we wanted to keep that the main focal point. Also with the piano on a 45 degree angle there's really no other spot for it, if we put it straight against the wall we wouldn't be able to open the cabinet doors in the built in bookcase.

What about placing the piano on the long wall, across from the soon-to-be-built fireplace, the long sofa against the windows, and the loveseat facing the sofa and the windows, creating a divider effect for the foyer. Then you could get a demilune table for the back of the loveseat. Would that work? I just don't feel the room is working with the piano at the 45 degree angle, sorry.