First off, I don't like the bed in front of the window like this. Are you able to move it to the wall where the dresser is?

Next, I would not go dark blue AND white for the walls, too choppy in a small space. You could go a dark blue all over if it appeals to you. I've seen dark blue in small space and can be fabulous. Gold or bronze would be an awesome accent as well.

I would actually start by springing for a new duvet cover and sheet set. I'd probably do a white duvet and sheets and a navy blanket at foot of bed. Some throw pillows with grey/blue/white pattern, also think texture.

Other things:
-My preference would be to stain the armoire darker to better match the dark brown furniture. You could also paint white.
-Bigger lamp on bedside table (gold or bronze base)
-If you are able to extend the curtain rod (some are extendable) - do it. I'd like to see the rods about 6" from the other walls. You may need wider curtains.
-Try to find another spot for the suitcases, like under the bed.
-Art hung 60" from the floor so it hangs at eye level. I'd go black frame white mat, some black and white photos could look great, or some stuff with color (and ideally the navy as well) in it.
-Get rid of that purple bath mat, and do a bigger rug.

Great ideas Cara. Thanks!