Add support to apply type restrictions on relationship bundles. (not to be confused with applying type restrictions or relationship type restrictions on the "related" item). This would be just like applying type restrictions on a metadata element, only on a relationship bundle.
This would greatly reduce screen/UI redundancy. Currently, we have to set up multiple, type-restricted "screens" in cases where the UI placement is identical with the sole exception of a relationship bundle that is broken out by type or relationship-type.