I’ve tried several systems over the years, and as a rule have gone with my NRS hydroskins. They are thin, offer good paddle control and have a contoured palm with a good grip surface. However, they’re not water proof, and when the wind starts blowing, they still let my hands get cold pretty fast.
So then I tried pogies from Kokatat, and those work really well for good grip and keeping hands warm. They’ll still let in some water, but you have great wind protection. The down side is some significant loss of paddle play, as your hands are pretty much isolated in one place on the paddle. Also, it makes getting to any gear a pain — cameras, water bottles, and all that. So they’ve been regulated to flat water days, when I don’t have to worry about adjusting my glasses after getting walloped by a wave!
For Christmas a friend gave me a set of NRS Maverick Gloves and these are the cats pajamas. They’re water proof, warm and still have a fair amount of dexterity. I was able to operate my camera, adjust glasses and helmet straps and have pretty good paddle control, including rolling. They’re the choice for me now in cold water/weather paddling in anything beyond flat conditions.