I vote a light grey instead - Revere Pewter, Stonington, or Grey Owl.

Functional gray looks a bit warmer. The only way to know is to actually paint a large sample on the walls and see which you prefer. However, that has to be done before there are decor suggestions, as it's hard to correctly imagine what the wall color will look like.

Here is greige Functional gray, I am not sure that it will have the same look on reality.

I look all the time on SW site when get a paint. There is great suggestion about coordinated colors.If look at Mega greige and Functional gray..they are both from brown family, but...no any color in your room coordinate with both colors. So i looked at similar colors and got Versatile gray with brown as coordinated color. That is closer what you have in room.

Then On the Rocks SW is more closer

As for Cara suggestions , only gray owl goes good with colors that

more or less present in room.