Host templates allow for dashboards 'prototypes' to be created, but browsing them is a pain. 

Can we have (non-prototype?) dashboards accept the pages from other dashboards?

Something involving a 'Include dashboard protype'-button when adding pages to a dashboard. It would make sense if you could specify a Host Pattern and Dashboard Pattern. The pages from the prototype would then be grouped like browser tabs, with a little border so you can tell they belong together. 
It would be nice to edit the protypes from wherever you include them, but a link to where they live would do.

This would allow a single slideshow to loop through host specific dashboard pages, without the hassle of maintaining lots of identical dashboards.