Besides carpentry, we are adding fixed glass windows at half height to the study room for visual connectivity between the study and living areas. ie living and kitchen. This also makes the room feels abit more spacious and more daylight penetrating through the areas. Glass always has this light and bright effect as compared to a solid wall which might be imposing to a small flat.
That being said, solid walls are good to have too if you need storage areas! Cos that's where you need to bank all your cupboards...all along whatever wall space you have.
my next post will be back to the mirror vanity again!