Thanks. I would need to fit a dining table and couch in the space.

my first thought is to mount the tv on the left wall (the one along the staircase going upstairs).

Can anyone suggest where the couch and dining room table would go?

You'll need a drop leaf table that can snug behind the couch and act like a sofa table when not in use for dining. I would wall mount TV on the wall perpendicular to the breakfast bar and float the couch and sofa/dining table perpendicular to the closet by the breakfast bar. They will delineate a traffic path from the stairs to the kitchen. For additional seating you may find a small bench will work under the window