It's amazing how warm a thin wool sweater can be, and a wool vest even makes it warmer. My vests were bought at Goodwilll for about $3.00 and are 100% wool, and relatively thin. They are perfect for that extra warmth around the trunk of the body.
I don't like coats with loose sleeves and don't wear them, even if very cold. You can keep plenty warm with light sweaters and a heavier wool outer shirt. That combination gives room for string clearance, but is loose enough over the arms to keep insulating. I still-hunt mostly and don't sit for hours in a tree stand, so I don't have to be completely idle.
I layer with wool underwear (Merino), A lighter sweater over top that...then a wool vest, and my heavy wool shirt. It has to be well below twenty degrees before I need anything more than that.
Keep the neck warm with a turtleneck shirt or a scarf. Another thing that I found really helps is an extra layer around the midrift area, like a wool or fleece scarf to keep the kidney area warm. It will add a degree or two to your body temp.