We are leaning towards the balboa mist.

I read elsewhere that if you paint the ceilings and walls the same color, the ceiling will look darker.

I just painted my ceilings a bright flat white, and walls SW Snowbound, which has that slight beige undertone that Balboa Mist has. I don’t think you can go wrong, but see if you can get a sample to test a swatch on the walls as whites pick up surrounding colors and look different depending on furnishings and N,S,E, or W exposures.