Hi Trevor,
The reason I think this is not a viable solution, is because Renovation, Partial Structure Display, Llayer and Layer Combo are all sorts of Filters. Today, if you notice a missing element on your Project or View Map, you have to check in 4 places, if you or someone put the element in the wrong place. So why not concentrate all the "Existential" aspects of an element in a single place? I call "Existential" aspects, because Visibility can be just one property (among lots of others) of an element, that can vary in innumerous situations. i.e. I may be modeling a very crowd building space full of MEP's and I just want to hide 2 or 3 MEP elements... In this case, if all elements have a Visibility Property, I can temporarily turn it off for those particular elements... Apply a Model Filter with a "Only Visible" Rule, and that's it... even though these elements share the same Renovation, Structure Function and Layer status with other elements, I just hide those specific. So, yes, allowing elements to be assigned to multiple renovation filter could solve some issues. But it would surely add another layer of mess to our workflows.