Maybe a good compromise is to work with the grey in your couch vs the wall color...brings in some color but won't overwhelm as a bold would. A linen fabric would be really nice as well.

Such a lovely space! I would prefer to see them blend with the wall color or lighter.

Hi! Its a great space and I can tell you have great taste, I love some of the furniture and accents you already have. For the window treatments I would definitely go for contrast! If you blend your walls will be out of balance, I would go for a solid medium gray or large repeat pattern (so it doesn't feel busy). Happy decorating!