Just saw
this recent post on another paddling board for what to consider when selecting a kayak paddle for one person who is 6'4'' and another who is 5'5''. I suspect the suggestions are coming from a whitewater paddler. When he speaks of feather angle, I believe it is related to whether a paddler uses right hand or left hand control of their paddle. The feather angle would be on the paddle blade opposite of which hand is exerting control of the paddle. This may be a consideration for buying a paddle after gaining some experience. I could be wrong about this since I don't paddle a kayak, but both feather angle and left or right hand paddle control are terms that kayakers talk about.