The stretch bone function of 2D Motion Key Editor is so limited and I find it very frustrating to use. It allows only the upper arms, neck and thighs to stretch which limits the animation to do any real squash and stretch motions. Animating something like front walk cycle with G3 is totally impossible. It would be nice if this limitation is rectified and perhaps better still, in addition, add a Deform tab like the Face Key Editor.