Both the stick and the throttle are great pieces of kit* , and give a good degree of fine control, but their movement isn't really damped. The stick shouldn't feel stiff in any direction though, mine is very easy to move in all directions. If your stick is sticking (ha ha) in places, that doesn't sound right to me. Maybe there is some foreign object in the half-ball joints somewhere that you can't see?
Something worth considering is putting some proper damping grease onto the joints. That would significantly improve the smoothness and control, and in the process, you would discover if there really was anything stuck in there that was causing it to catch when moved in a certain way. I have a post with a link to how to do the greasing
here if you're inclined to go down that route.
That said, if you've not had it that long, and it has always been stiff in some movements, maybe replacing it under warranty might be an idea.
Hope that helps!
(*) Except the yaw pots. They're rubbish