Its good to see progress in the widgets management. The new mp6 page is most useful when using it on a large screen. It seems a bit random the way the sidebars/widget areas are arranged in the 2 columns now.
I miss a level in the way they could be arranged, if there would be a way to create containers and then assign the widget areas to them things could be much clearer.
Being able to have like: Frontpage, Footer and Sidebars as container elements might simplify the page. (ideally with the ability to create them like menus)

Alas I am afraid that implementing them in previews is adding clutter/confusion