How about some wall decoration upgrades that are windows and show through to the backyard background? Multiple style/shapes could be available, but with the "view" dependent on our the background we've selected for our yard.
+1. I have three starry "windows" in my 2nd floor, and they look incomplete without some sort of trim, even with all the furniture and hangings I used to disguise their plain-jane feel. (I know, you mean "real" windows, ie, to the outside of the house showing the backdrop. I'm all for that, just mumbling...)