Like objects in like positions
Sets of slides are usually comprised of the same layout with different content. Always maintain the same positions of the fields/chart elements within the layout for a set of slides. Excessive content on a slide may demand that the positions of the fields/chart elements change, but this would be the only exception.
As you move from slide to slide in a presentation with sets of slides, you don't want the fields/chart elements to snap to different positions. It is disruptive to the flow and evidence of a thoughtless development process. Before you present sets of slides, view the sets in slideshow mode to see if they remain in the same position. If not, make the necessary adjustments so that they appear in the same position.