What a fun space! Love the pillows...I agree with above, lower all the frames, but not so low little ones can reach. The art should fall at eye level about 5'4" for walls and for behind the sofa not more than 12" above it. Then keep the width about 5" inside the sofa length on each side. Your frames are small so you need the close together for impact. I would start with some pretty curtains for the door and large window and then a simple Roman shade for the small window- since your girls play there you don't want anything they will grab hold of. http://www.houzz.com/ideabooks/query/how-to-hang-a-photo-gallery

Now for Mr 16 months... I really can't decide. His room is going to be on the cold side of the house, with not so much sun so I want it to get that cozy sort of feeling when you come into it. I was thinking yellow or orange curtains? But then I don't know what colour to do the walls. These are some fabrics I like:

I quite like the colour scheme, it's looking good!

I'm going for a minimalistic boho bedroom but I'm stuck on if I should do light pink or dark blue gor ascents around the room or I could just go with what ever. Thanks