Here is an interesting idea. These are called wrist huggers. You could wear something like this over a thinner fleece glove or cycling glove to maintain dexterity and then add a glove shell to block the wind.

This would keep your palm and wrist area very warm as they would have a thicker amount of insulation and would keep the pulse area very warm. But because the fingers would have fewer layers more dexterity is maintained. These can be used under heavy ski glove or mittens also.

http://www.boothuggers.com/WristHuggers.html