Going for soft whites and beiges, even a grey that has a warmer undertone is the key to keeping it cosy, rather than going for a cool undertone. Think toasted tones like Granola, Salt of the Earth and Crème de la Crème. Avoid stark whites, which will take away from the cosy and calming environment.
When thinking about furniture, consider adding pieces in beautiful antique pine, to bring texture to the room. Steer clear of pine with an orange varnish on it, and stick with natural pine, which has a clear wax on it, letting the natural patina show through.
Alternatively, you could try a dark, rich wood, something like a cherry wood, to help keep things clean and elegant, but also add depth. It could be a chest of drawers or a coffee table, an accent chair, or even the base of a lamp. These touches add layers and cosiness, without overwhelming the space.