What's the hassle?
I've just upgraded a project to Atlas UI, where I needed to manually change each page layout for 100+ pages.
What would be nice?
1. A wizard to change the layouts of all pages, where you get a list of all current layouts in use and for each/all/multiple of those you can select the new layout
2. Multi-select a couple of pages, add an option in the context menu to select a layout for all the selected pages
Project > Tools > Batch Layouts ?