More Walls

Because I am hermit-like and want doors behind which to retreat from the madding crowd and am obstinate enough to insist on it, our second floor (not loft) bedroom will have walls and a door.  Call me crazy, but the idea of having my bedroom open to the world (even if you can't see in from the first floor) doesn't appeal to me.  So, Intrepid Husband is crafting the front wall of our bedroom.  Ain't he a nice one?

So, since we're going to have this nice wide balcony overlooking the living room and looking out over the lake and such, I need some ideas on what to do with it.  Line it with bookshelves?   A big mirror that reflects the windows across from it?  Squashy armchair and reading light?  Desk and work center?  Murphy beds for when the cousins descend on us?

Help!  I need a general idea so that while it's being built, nifty features can be accommodated! 

Thanks!