ArcMap has a "Change Layout" button in the Layout Toolbar. This allows users, who need to switch their layout format, to choose a custom template from a folder location.
Scenario - I built my map with an 8.5x11 portrait layout. My client is now asking for the map layout to be 8.5x11 landscape. I click on the "Change Layout" button, choose from my catalog of custom layouts and I've quickly, on-the-fly, changed from one custom layout format to a different custom layout format.
In an ArcGIS Pro layout, I am not afforded this "Change Layout" functionality. Yes, I know that we can have multiple layouts in a Pro project. I'm looking to be able to pick a custom layout from a folder of custom layouts. Not "Import" an additional layout from an mxd document.
I would love to see this enhancement in a future build of ArcGIS Pro.