I’m not sure why but I do have a love of sun and shadows and so for window coverings I will always bear that in mind if the room faces south or west. And if it does I like blinds that give shadows such as Venetian, new double roller blinds with sheer panels , shutters and I’d even consider vertical in the right situation. It also depends on what time of day and what purpose you use the room for though. And if you’re overlooked, especially at night. I once had a west facing living room with mid “golden” coloured wood venetians and in that particular room the afternoon evening sun gave a magical effect. I’m not suggesting you go for that , just that you think about the light??

i don't think it would look silly. Dark Blue is a good choice for a north facing room. instead of trying make it white which can end up looking grey, it's a good idea to embrace darker colours. if you add the living room with white and grey accent accessories and bring some dark blue accents into the kitchen (curtains, blinds, baskets, dinnerware, pottery) and bathroom (wallpaper, rug, tiles picture etc), the whole space will have a same feeling. just create a connection. you need to look at the space as whole. http://www.farrow-ball.com/light-affects-colour/content/fcp-content

This was in 2011, when we just started renovating. Top windows are new (ral7039), walls ral9010. You see the neighbour on the right has bright white, the attached on the left some creamy tan. (Landscaping credits go to previous owner..) Don't have many new photo's, but this was a few months ago, when we had the front door and livingroom window done too (pvc): Lower edge on the wall still needs some paint.. And landscaping hasn't been done yet either, but we did take out the dug in roof tiles.. (plus we're slow renovators LOL no stress)

I would suggest leaving the green scheme in situ at the moment as it think i see green flecks in your material swatch. Going blue in wall, curtains, and furniture, althought it seems coordinated,  might end up being too matchy matchy in real life. The green flecks may actually be better co-ordinated than it initally appears and the furniture may actually bring the room together.