It's a tricky one. I kind of went for some middle ground between the normal/hard modes in WaDF (I prefer the hard mode myself, but added the normal mode which more damping so the game would be easier to play). In Underground, I figured that with Mi, she could provide accuracy and deceleration. Since the ball is mainly used to do tricks, I wanted it to be easier to maintain a non-full horizontal speeds. Basically, I experimented quite a bit before I came up with these exact settings, and just landed on whatever I liked best. However, I understand it may not be everybody's thing.