Camera was repositioned in update() (before the physics step synced the sprite), so it lagged the player by one frame; on fast ascent/rocket that read as the character trembling and breaking up. Move camera follow to a POST_UPDATE (lateUpdate) handler that runs after the sprite position is synced. Verified on-screen jitter while the camera is latched is now 0px (was ~one frame of vertical speed). Also prevent squash-and-stretch tweens from stacking on rapid bounces (stop any in-flight squash before starting a new one and on powerup/death transitions), which had made the sprite scale pop.
AnRil
7c6a792212