1. Is a full wall of curtains so you can't tell the window finishes short..
2. Just white shutters like the rest of the house
3. A feature wall paint with a textured roman on both walls....the taller window wall also the wall that has the door to the WIR so this is not ideal to paint any other colour aother than the wall colour( a white of some description)
So please share your thoughts ideas or photos.....
the other issue of balance is that the window on the LHS finishes lower than the RHS and the LHS corner window .
Also having windows that meet at the corner can create some challenges. For instance having roman blinds on both walls, and with what looks to be a small recess means that the operation of each blind will interfere with each other at the corner. It would also create light coming in at the corner, which may be an issue for you.
You could have shutters and then dress curtains (floor to ceiling), but it is a little difficult to see proportions when I can't see the full length of the wall.
You could have a curtains on the LHS, made that when pulled back it covers the smaller square window in the corner, thus emilinating the difference in height in that wall. Blind or shutters then could be put on the RHS wall.