There aren't that many up-scrollers! It would really help the feeling if the scrolling sped up when one is in the top 20% of the screen or so, because having to play through the tutorial gets sort of tiresome. If the character could stop the X-movement much faster when letting go of A/D the controls would feel more natural. I like the slicing, but since one need to cut a few times it would be neat if one could see some effects on it. A good start!