I would like to file a feature request.
We are really fond of using the Property Value List (https://world.episerver.com/documentation/developer-guides/CMS/Content/Properties/property-value-list/).We have experienced a problem when using this with LinkItemCollection- or simple ContentReference properties in a Property Value List. When deleting a page which has a reference to it through a Property Value List, the GUI doesn't report the page as having references to it. I know this isn't one of the supported properties in the Property Value List. However, it would be really nice if that was possible. Using lists is very handy, and is a much better solution than to reference pages which has properties on them which is used in certain scenarios.
We had a support request regarding this (https://support.episerver.com/hc/en-us/requests/263589), as we thought it was a bug, but looking at the documentation, we can see that other properties than String, Int, DateTime, and Double isn't supported.