remove the valance.

Paint the fan to match the ceiling and the upper trim to match the wall. If the space is going to be dedicated to St. Television, the you have to determine the most sensible place to mount the screen at or slightly below SEATED eye level. Once that's established, you have a better sense of the number and kind of seating pieces you need. Anchor the room with a generous rug.

I agree with jbtanydenri about the ceiling fan and molding. You could also give the whole room a fresh coat of paint maybe something colorful. Not sure how much you want to do but you could also update the windows into maybe one large window with white trim.

Are you looking to keep the fan or would you look into replacing it with a light fixture instead? You can look into many alternative fixtures that would still bring a lot of light into the room or look into a different fan altogether if you want a more contemporary look. Painting the fan is also a good idea per jbtanydenri.

Not sure how much you want to do with this room, but you could consider replacing that window with a large bay window, could even allow it to have seating in it. Painting the room, trim and ceiling fan may help it as well.

If the intent of the room will remain a den you could paint the built ins along the wall.

Option 1 - Paint the built ins navy or indigo (or stain them espresso or something dark)

- strip and refinish the floors a lighter tone

- remove the ceiling fan and add recess lighting

- paint the trim lighter

- paint the walls a neutral color

- remove the valance and replace with bamboo shade or roman fabric shades

- you could fit a love seat in or a setee in there (a 2 seater sectional could work too)

- put a large area rug in the den

- put a nice leather office chair for your working space

- put a nice large floor lamp in the left corner of the built-ins along the seating area

- show off the window sill and display some plants on top

- to the right of the window hang a nice piece of art work on the wall

Option 2 - Paint the built ins white or beige

all of the changes are the same as option 1 except, you do not have to strip or stain the floors, keep them the same