(LIVING ROOM: couch + coffee table accents)--gray couch couch, as well as the gold & white accents which would blend nicely with our color scheme (peacock/aqua blue to match your chairs, peach pastel, and white).
The space under stairs is always cool! A nice cozy hide-away would be neat, a platform type thing with maybe dark pallet in the background
Ceiling Shelves - built-in shelving that utilizes the vertical space just below the ceiling. This is a brilliant use of space + 29 Sneaky Tips For Small Space Living - via Listotic. I love that couch.
Stairwell - ledge, frames, books, etc