Perhaps wooden shutters installed outside would work. They'd look amazing and fit in with the look of a barn conversion too. Then, you could still consider the louvre drapes for the inside, but keep them open, only closing when you want privacy. So in this way, they are really being used for 'dressing' purposes only. The reason I'd put wooden shutters in, is that you wanted to dress your window, and since this is a barn conversion, the window rests on the floor and is not conventional, it calls for unconventional dressing. So, shutters will add interest and depending on how high they are from the bottom, outside, they could be used to close up for privacy, but if too high up, then used only for effect, and the louvre material drapes inside to match your décor. You could use short curtains, but as I said before, you'd have to tie them back so that your window can open, which would work find as well. perhaps draw it out, using the various options that you've been given by everyone, and see what appeals to you? You could make this window a feature, which is what I'd do, instead of 'just a mere small window' and really make it a 'wow' feature in your room! don't be afraid to be brave with your décor on this one. have fun with it!

I think some beautiful white voile for the day time, mounted on a very discreet ceiling mounted track, such as Silentgliss, which can be bent into the bay. I would then put a bay pole in front of this with whichever curtains go with your scheme, using a blackout lining. I would be careful not to have the curtains gathered too full though as you do not have a lot of space to the left of the window to pull them back. Although unconventional, to overcome this problem, you might want to consider having the curtains made to different widths, ie a shorter left curtain and a wider right curtain so that when they are closed they meet at the corner. On a flat window this would be very conspicuous, but your window is unusual.

Hi, how about a double wall to wall track with sheets on one and blackout curtains on the other?

Hi quick sketch attached which hopefully will get you thinking on non standard options to avail of the triple aspect and views. The bed is centred on the West facing window, so even though there isn't symmetry in the rest of the room, balance is created, focused on the bed. I've shown a freestanding headboard behind the bed - something along these lines....there are design options available which means no need for a bedside locker to the side. I've stolen a small amount of space from the adjacent bedroom (sorry kids!) & pushed the entrance door back into the hall slightly. There is no door to ensuite, but the curved wall which becomes part of the shower creates an entrance & cuts of what you don't want to see (the wc) but allows light in, views out to and from the North. This curve also creates a natural line to change floor covering - say from carpet to tile. Theres approx 5m of wardrobe tucked under the eaves with curved ends (if budget will allow!) and also His & Hers drawer sets either side of entrance door.