This type of roman shade would be a nice alternative. I think you should stick with something that fits inside the window as you've already done since the space between the bed and the windows appears to be narrow.
You could stick with something like you have but a little dressier such as the second picture. Or you could hang the same thing from half way down the large window and match the height on the smaller two and then put a colorful valance at the top--something with red in it.