I like the contrast of the Balboa mist. I think that will look awesome!

I vote Balboa Mist for contrast. Abbey Road looks too close in value to your main color.

Because the floors and other furniture are very dark walnut, I think all 4 walls would be tranquil at night with soft light, but way too dark in the day. It wasn't so much to "accent" as to have one wall break up the dark.

rather than changing strips, if you want Balboa Mist (which i love), go with River Reflections (1552) instead of Arctic Shadows. or if you want Arctic Shadows, use vapor trails (1556) instead of Balboa Mist.

Vapor Trails and Arctic Shadows have a more blue/green undertone than River Reflections and Balboa Mist.

I think you need to know what the undertones in the wood of the headstand. Is there gold, red, etc. Then know what the undertones of the three paints are, which you can see in the chip or ask your shop. Sounds ponderous, but I like to be precise.