Brown. Dark brown and pale blue look amazing together. I've done one room in my house with this color-scheme and now want to do another. The contrast between light and dark works well and together these colors are soothing and relaxing.
White or off-white (but not ivory...too dark), natural woods, shades of navy blue or slate blue, sage green. Touches of orange or golden-yellow if you like those colors, but that's usually where I like putting wood . Just pick a color or two you like, though, because all of them in there would look pretty horrid. I've actually found this tool to be very helpful for decor, jewelry design, putting together outfits, etc:
My favorite colour is brown and other earthy variations of it. Blues in different hues including aquas and teals can come together for a lovely combo as well. Both are reflections of nature which I find soothing.
I agree that browns go really well with pale blue but what also can go really well is different shades of green and really pale yellows. Depending on the actual color of your walls, some different shades of purples could go with it too. Bring some paint swatches home to play around with shades and that will help you decide. Is your room carpeted or does it have wood floors, because that will make a difference too.....wood floors open up the color choices.
I think light green, yellow, white, light pink etc. could all go nice. I would say look for a quilt or comforter which has pale blue as well as some other colors in it, and then do accents based on that. That way you know it will match cause someone else already thought it did!