I’m thinking of painting the master bedroom and bathroom a gray blue

I've just painted my living room and hallway a blue-gray. It has come out fantastic! I strongly suggest using the lightest shade as the walls will darken up with time, I am now going to paint my master in FL using a truer gray.

We have a blue-gray on our ceilings called November Sky

That sounds like lovely color choice! I think blue bedrooms are very serene and peaceful. I miss my blue bedroom.

I personally think you should go to a paint store and pick up some color swatches. Get any that you like. Come home and tape them to the wall and look at the in daylight and evening. (You might need more than one of each, if they are small) As you look at them in passing them as you move through your home, you're going to look at some and say "No, I don't like that one". Take it down and throw it away. Keep doing that, always removing the one you like the least until you have 2 left. Then make your choice from those. No matter what another person used, there is no guarantee that you will like it. Wishing you the best!

Very popular color choice - on trend and very soothing!

"Grey Cashmere, Benjamin Moore

“For me, this is a no-fail selection. I’ve used it in bathrooms, kitchens, garden rooms, and bedrooms - all with beautiful results. It has the perfect amount of blue saturation to pair with bronze, green, periwinkle, or even spice. I prefer it EXTRA glossy on paneling!” - Meredith Ellis Here is the site and I also attach a color shot.http://www.elledecor.com/design-decorate/color/g3233/grey-paints/  ; Please check it out in person as my computer may distort this gorgeous color.

Paint colors are very personal. Your best plan is to choose color charts,see what works well in your home with the lighting etc,once you think you like it buy a test sample jar. Others cannot and should not advise colors. This is your home. Remember lighting plays a big part of color shades