They both look like a shade of gray, one lighter and one darker, on my monitor. I am not fond of either of them.

I have used both SW Comfort Gray and SW Acacia Haze in my home in the past. These are quite similar to the two FB Colors. Comfort Gray is one of my favorite wall colors, but it is pretty light for cabinetry - I would most likely go for the darker of the two.

I like both colors and have similar (Blue Gray) in my kitchen. I voted for Light Blue here because it’s lighter- I love Pigeon, too. The fact that they are both muted an grayed is a plus,IMO. I’ve used both F&B and BM in my home, and I have to say that the F&B is definitely more nuanced, changeable over the course of the day, and therefore more beautiful- to me.

Very dull colors but in reality, which color of these you use depends on what furniture you will be using, how your furniture will look with daylight and night time.

I like both, probably lean towards the lighter though,

Farrow & Ball paints are my favorite, they seem to have a ”depth” that other paints don’t have. I don’t think you can go wrong with either one.

Lots of sun does like darker tones, especially when chosing an accent color. Why? Because sunlight can wash out lighter colors, IMO.

https://www.matchmypaintcolor.com/benjamin-moore/blue-spruce-1637/farrow-ball-matches

I don't like either. Too depressing; just looking at them on my monitor makes me feel saddened. Take your cue from the colors in your artwork -- there's a lovely soft blue in there, or if you want a richer color, there is the deeper, more saturated blue. Neither of those would make me feel like committing suicide.

I'm inclined to like the lighter of the two colors more with your floor.

How much contrast do you want with the cabinets and fireplace? If a lot of contrast go for the lighter color, if not much contrast go for the darker.

In a small room, I'd prefer to color drench the whole room including the bookcases in the same color. It looks like you want a woven wallpaper though, yes? If so, I'd select the two in tendem. Get your FB paint samples, have them with you while looking for your wall coverings, see what sings.

Gray is gray. Not what I would ever choose.

Not a fan of either but your furnishings and natural light might make a difference.

Won’t feel cooler, but perhaps potentially drab.

Could feel dreary as well.

Maybe consider a different undertone and paint larger swatches next to each other of your top choices. Compare during different times of the day and with the lights on. F&B have excellent consultants and in my experience they easily narrow down shades based on what info is provided to them.

If these are the only choices, then Light Blue wins.