It would be great if there was a way to export and event sheet, including all objects referenced in the event sheet. And then support importing an event sheet to a new project. This could come in two flavors:
a) export of an event sheet that only references invisible objects such as Dictionaries, Arrays.
b) exporting of an event sheet that is linked to a layout, in such case both the layout, all objects on the layout and the event sheet are exported
there could be a third flavor
c) event sheets not linked to layouts, which neverthless refer to objects on layouts. here perhaps the object type can be exported and imported without placing it on any layout, during import. As if "all instances" of the object type were deleted.
In the future, to allow for real reuse, it might be great if there are linked event sheets -- where event sheet sources are shared across projects.