This is well presented and all the elements are there...except for the theme. Sure, I could alter my pitch but not really my rotation, at least when I consider that a rotation is usually perceived best when performing rolls (or rotations on the Z axis). I though I would do a flip if I had enough headroom and maybe that would give me a boost in speed or something like that. I think that would've been the mechanic that would've sold me on the them "Rotate up/down to avoid the enemies. Perform a full rotation to get a boost" ;)