I looked at door on houzz for a short time. Seems as though a few things come into play. If you want to accentuate the vertical lines of your entrance, go vertical. If you want a more understated look whereby we see your door and panels as one -- then go either same color as door on the handle if possible and the only things showing will be the lock. I prefer a smaller handle or a horizontal plane for a handle because horizontal is a more relaxed look. vertical creates tension. So, look under: Photos, then Modern, and type Front door in the search parameter. Hope this is helpful. :=)

With a sliding door, you can have each side different to match the style of the room it faces. Here are some ideas that, believe it or not, are done with sharpies on flat surfaces. I can envision a "fireplace" on the lounge side. On the dining room side, you could do the "double door" look, by putting half on the door, and half on the wall next to the door. So when the door is closed, it looks like a pair of doors, but when the door is slid open it looks like only one door (but it's the wall!) I added the 3rd picture just because I think it's so cool. I believe the only "real" thing in the room is the glass table/desk, and the filing cabinet.

Paint the wood floor with a flooring paint. If you want to be creative, you can create your own special design. I've had painted wood floors in a previous home and everyone loved them. If you get tired of it, paint them a different color! Saves doing rip out and better for the environment! My floors held up well. I was surprised. I even did a faux marble floor for fun.

Get a piece of wide shoe moulding for the bottom trim. Add organizers and shelves, paint it white white with a coat of satin polyurethane over the paint, and add new hardware. It will be beautiful