Much how there is OD, AR, etc that affect the difficulty of patters, I propose to add another component: instability factor. This would control the intensity of the fruits shaking or wiggle. While this effect is possible to intensify with the HR mod, modders are not really able to control this aspect. By making this an independent component there can be maps that are slow, high CS, and have the said set instability for instance. For the most part, this would require a lot more precision than what high CS requires since it will be moving back and forth as it's falling down. Sounds like an interesting concept to me.