Would you say your hands are often cold when you are otherwise quite warm? I ask because I think it is important to differentiate between a situation where your hands are cold to to poor circulation despite you r core temperature being fine, and a the situation where your core temperature is dropping and your body's natural response is to give priority to the head and core and reduce circulation to the extremities. Solutions for the two are quite different.
If your body is reducing blood flow to the extremities due to your core being cold, warmer handwear won't help much - you need to keep your core warmer -, but if your circulation is just somewhat less than normal all the time, then warmer handwear will help more.
As far as the actual handwear, a nice liner type glove (i'm using powerstretch lately)and then warm mittens - fleece or pile or wool - and then an uninsulated mitten shell, is the best combination I've found. Versatile, since you can wear any piece separately or in any combination; faster to dry if any part gets wet; and when you need all 3 pieces at once, you still have the ability to take off the mitten layers and keep the liner on for quick dexterity tasks.