DIY most beautiful girls' closet I've ever seen - Love the idea of painting the inside of the closet a different color than the room. Especially the blue and pink. I want to build shelves just like this.
Awesome Loft Beds--Since you won't have a window on the one end of your upstairs, this could be a fun idea for the kids area. Not necessarily a bed, but a 'loft' on top of a 'hide-out' area---or something. The bookshelf stairs are a neat idea too.