It would be very helpfull to change the order of page elements in the right pane with drag-and-drop.
I have made my templates mobile responsive, as far as possible with Marketo's absolute positioning (e.g. http://connect.quintiq.com/rail-executive-seminar.html). It basically puts all "lpeCElement" underneath each other with 100% width. But this requires the page elements to be in a specific order. Else the all texts would be not chronologic. You could make sure to start building your page in the correct order.