Add the ability to not only show/hide references and nested references but also to "unload" them so they don't take up too many resources. Right now there is the option to detach a reference (which doesn't work on a nested reference I believe). But it's so permanent. If I'd need the reference again later I'll have to search for it again, maybe translate/rotate again, add clipping again, ...

The use case I have is the following: I always make a model called "Underlays" which contains one or more references (DWG, IFC, ...) from other sources as underlay for my current design. Now depening on which model I'm working in I will always reference the same "Underlays" but will not always need all of them in each design model. But they are all loaded which takes time when opening the model and eventually slows down Microstation (/Openbuildings Designer) when there are too many references, even when they are not all showing.