I suggested having the triangle (slightly) more on the back of the hand (about two edge loop above, on your pics), not on the wrist itself, where it will not deform nicely when you'll animate/pose the model.

there's also some slight proportion issues there I think. The four fingers seem just a little bit short, compared to the palm and the thumb. Or maybe its just the thumb that appear slightly big, I'm not sure. Otherwise, good progress.