You could try a traditional barn paint, such as milk paint. I've used Original Milk Paint before and it looks great! Not sure if can be used on an exterior, but it will certainly give you that color!

Catherine the panel blinds could be your solution. They are available in sheers, patterned, mixed etc and operate on a track system. It's an update of the verticals that a lot of homes have. If you have Ikea in NZ you could sus them out there.

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

There was a similar discussion last week, maybe you can get some ideas from it: https://www.houzz.com/discussions/help-for-exterior-cedar-siding-trim-color-dsvw-vd~661559