My parents house is south facing, and while the kitchen is warm, the north side is very cold, and never comfortable, I don't think it's a great orientation. Our own house is pretty good, the kitchen faces east and gets sun in the morning, the sitting room gets sun in the evening. However, I think the ideal is a west facing garden. That way you get long bright summer evenings in the garden (weather permitting!!!!) and most of the house gets some heating from the sun. If you work all day, you still have the sun in the garden in the evening when you have some chance of enjoying it. It means you don't have a dark depressing room in the house (hopefully).