Your reps said that an intentional delay was put into the edge scrolling because you expect people to use WASD (even if it's not comfortable for them) so I have to wonder if the delay in the right click menu is also intentional for some odd reason.
The edge scrolling should be fixed to be more responsive and less delay. Because I dont want to use the WASD keys, it dont feel like I have the same amount of control with WASD keys as the mouse whens scrolling. I mean the delay is just silly and not bringing anything to the game at all.