1) "Dumb" is a pretty universally accepted term for tags/annotations that aren't linked to any parameters, as OP has been doing. I'm not referring to what you're suggesting.
2) I understand what you've been saying the whole time. My point was that implementing your idea would be extremely time consuming while adding little additional functionality. For one, OP has explicitly stated multiple times that while cabinets were their example, it is not the only use they are looking for. But ignoring that, all of these parameters would need to be added to EVERY casework family they have. And even then, you need to manually drag all of those reference planes to the adjacent elements for it to work properly. And looking at OPs posted drawings, this isn't something that would be in a single tag type. They have the offset tagged at each offset point. Meaning the appropriate type would need to be selected for each of those offset points, leaving room for error.
Sure, you can lock it so if things are nudged, it still reads correctly. I suppose that's one step above a dumb annotation, but just one.
OP was wanting a way to be able to tag the offset distance between any elements, and the answer to that is that it is not possible. I think it could be a handy feature to be implemented though.