I agree with painting the wall behind the sofa dark gray. That will make a great accent wall!

Instead of painting walls consider a larger print for over the sofa. Hang it lower 6 to 8 inches over sofa.

if you are still set on grey, consider BMs balboa mist instead of edgecomb. i've used both, and balboa mist is a tick lighter in weight, important when you are surrounded by it.

I love gray but IMO the gray will make your room too dark and dreary especially if you also do a dark gray wall. Maybe a 50% cut revere Pewter which has a bit of a brown in it for all the walls might work the curtains like mentioned above. Hang the T.V. on the wall get a long low T.V. stand in white and an area rug in white and orange and Paint the DR set white it will feel like a new space .Add a much larger piece of art above the sofa and hang it lower