This feature is a already scheduled for e!Sankey 2.0. So far we have not decided if it will be realized as a process option or a separate process type. We think that most users will not combine autoscaling and fixed size processes in one diagram, so it may be easier to handle this with different process types. Additionally these process types will behave differently: While fixed size processes snap to the grid with their vertices, autoscaling process need to have aligned by the center point.