Optionally deliver regional mbox offers via global mbox

Our developers do not like the excessive number of calls required for each regional mbox inside of our SPAs, however they like the added structure of regional mboxes for offers and personalized content. It would be nice to be able to return regional mbox content setup in the Form Composer via the global mbox. For example, a list of mbox names could be passed as parameters to the global mbox for a particular page/route. The global mbox could return the content for each of those mboxes listed in a single response instead of using multiple regional mbox calls. This should be an optional setting for the experience.