I like the overall layout of this unit. I dont mind the den being open to, or part of the hallway. I bought a place in Axiom with a very similar den open to the hall. A closed den for me becomes a catch all of clutter that is easily hidden away. I envision for this space that the den would have a wall of Ikea Pax woredrobes and perhaps one of the systems converts to a desk when the closet doors are opened.
My dislike of this unit is the small second bedroom, and the overall living space seems narrow at 9'9" . Otherwise the living/dining has enough room length for both dining and living.