Is this still being looked into?
I really want to play this game, but this sluggishness involving the mouse infuriates me to the point of craving to play other games that don’t suffer from this issue. Even scrolling the chat box is affected by this (presumably artificial) smoothing.
I call this kind of smoothing “Apple syndrome”, as their users seem to enjoy this sort of stuff. Gamers don’t, however, and it wouldn’t surprise me if many seasoned gamers have left this game purely due to this issue.