I broke down and ordered the Ibex Cortina loden wool vest in apple green:
http://www.ibex.com/Photos/F06/208_2722.jpg
It's on sale:
http://www.ibexwear.com/shop/Product...t=Cortina-Vest

I wear my orange Switchback vest so much, I wanted another heavy wool vest in a different color.
I find that wearing a couple of wool longsleeve tops and then just a heavy vest over them is really nice for being outside in about 30 degrees. I don't overheat because the air can circulate a bit around my arms, but the vest keeps my core very warm. And I can move freely- great for fitness walking. As long as my core, head&neck, hands, and feet are warm, I usually feel ok with a bit less on my arms and legs.

By the way- the Ibex "Ribbies Crew" just went on sale in various colors:
http://www.ibexwear.com/shop/Product...&Gender=Womens
...not to be confused with the thinner "LW Ribbed Crew".
The Ribbies crew is pretty thick and nice. It has a finely ribbed texture. Runs a bit fitted, so order a size up from your normal if you like it relaxed fit. The Larkspur color is a beautiful intense twilight blue- I have one myself. The Sand would look nice layered over a black turtleneck.