I think this has been asked for before, but it would be nice to have a custom property type that could store a list of asset references. Even a list of strings would be ok. My personal use case is that I what a template that will spawn random assets on a triggered event. Ideally I would have a custom property on the group/item that was a list of asset references. Then on the triggered event it would grab the list and randomly select what to spawn from it.
I could then reuse that template throughout my hierarchy and just change the custom property asset reference list to the appropriate assets for that area.
The current workaround is to just add a bunch of custom properties to a single object that I can then find and randomly select from, but it's clunky and not very intuitive to maintain when I want to just drop in some new assets as I create them.
An alternate solution might be a way to group templates in My Templates so I could refer to them in script by name or as a custom property with type "template group/folder" or something like that.