Windshirt: Montbell UL, women's large (with any other mfgr, would be a medium)--2.4 oz. I originally bought it to keep flies from biting through my shirt (they regarded the permethrin treatment as an appetizer), but now consider it the most versatile garment I own. In cold windy weather (low 50's F to 25*F), base layer plus windshirt is what I wear when I'm actively hiking. I stay warm but I don't sweat. As it gets colder I add a Smartwool headband for my ears and lightweight gloves. The windshirt also adds some warmth to my puffy jacket during stops or in camp. In warmer temps (60's), the windshirt is my in-camp/rest stop layer.
Sun hat: Another Sunday Afternoons Adventure Hat fan here--2.8 oz. I don't have to use sunblock (I'm allergic to sunscreen) unless I'm where it's reflected upward--water, snow or above timberline on mostly bare rock or soil. It has a nice broad brim that doesn't flop much in the wind, and the drape in back keeps it from banging against my pack. I can also pull my rain jacket hood over it, so it keeps the rain off my glasses. I really don't care that it makes me look like a mushroom!
The dri-ducks stuff is OK if you can stay well away from any brush. Take some extra duct tape--you'll need it! As others have said, it is breathable but not nearly as much as a wind shirt.