How awkward and unfinished can a builder make something? Surely this was a builder boo-boo and not on the real floorplans! Decorating is not the first issue, but remediation is. See where three different pieces of trim meet there on the left and right! That's the place to try and sort out. It may be better to simply prime and paint all of these awkward trims the same colors as the wall each one trims out and try to ignore it. If you can paint the flooring they've installed, match it to the bottom wall. IF it won't hold paint, remove all the trim and the flooring. Better to paint subflooring with floor paint than this linoleum looking piece. I'm assuming the builder put subflooring there, but would be in doubt of that!! I definitely would not try and decorate it. That will just bring the eye up to see the goofy job your builder did. Make it disappear and focus the eye somewhere else. Would you want to consider stained or decorative glass in the window? Paint the foyer ceiling a pretty light blue. That works well with brown and will take the eye past the eyesore. Can the fixture be raised to be seen through the window from outside and draw the eye past the area when you're inside? Right now it is hanging where it draws more attention to the goof! Would you be able to light the lower entry with sconces to match the ceiling fixture if it doesn't adequately illuminate the lower space when raised above the goofy part? Even a foyer table with two lamps would help keep the eyes downstairs. Just pull the eye elsewhere and pretend this never happened. Sorry, to be truthful about it!