Fleece beats wool, for me: cheaper, lighter, doesn't get waterlogged, stays in shape if wet. If you avoid premium brands it is dirt-cheap; the fleece may not be Polartec, but it will still function well as a mid-layer. Windbloc fleece (two fleece layers laminated to a Gore-tex midlayer) is a great for winter jacket. The Gore-Tex layer stops the wind completely, and is waterproof enough to cope with snow or light summer showers (You can't seal the seams, so it can never be fully waterproof). With 'pit zips for ventilation you get a jacket that can be worn over a great range of weather conditions.