If you're gonna do Isometrics, DO IT RIGHT.
Listen, this game is difficult on a degree that it isn't even fun.
Reason being: the ball does not move in accordance to the camera angle.
Listen, what you need to do is make the left and right controls TWICE as fast (in acceleration and decceleration) as the up and down controls, then the controls will work properly like they aught to in an isometric game.