I love the subtle gray stripe on these steps that tie into the room beside it. A painted runner can add a little something extra to your steps without the cost and installation process of an actual runner.
Two toned steps really make this staircase so elegant. I love the dark and light that flows throughout the house and making the stairs match really ties it in with the rest of the decor.
via Adore Mag
via Southern Living
A staircase is a great way to showcase art too. Gallery walls have an especially big impact.
Another option would be to change out the railings for something new! This can really change your view of the stairs depending on what you choose like these thinner railings above really make the stairs feel more open.
If you're really ambitious, consider wallpapering the stair risers. I love this look, but I wonder how durable it is.