My thoughts: Door way on the left and door on the right and all door and window trim and ceiling should be a true white. Then all the rooms could be another color -- a light to medium flat or matte color (not another white or off white). Look in your closet an see what color shirts you usually choose and consider a shade of that color for your wall.
What is your hobby or primary interest? Add something to the wall that reminds you of something you enjoy.
Don't forget to do some thrift store browsing to see if you can find something you like at a bargain price.
Something like "sun" could be left the muted copper color or painted bright yellow or bright red against a pale blue wall.
If you like music, there is pressed metal wall sculpture for that:
... just google "inexpensive pressed metal wall sculpture" and then add a subject "sun" "music" or whatever your interest.