Point controls of corridors while working from an active reference drawing that doesn't use feature definitions

This is what I am doing - Creating featurized versions of the original linework for modeling controls. I create design horizontal features from the original drawing lines with an offset of zero, so they are ruled to the original graphics. That way, if those original elements are modified, the design elements can follow them to keep up with changes. It's not foolproof, but it somewhat isolates me from having my design fubar'd from someone deleting those other graphics on accident. When a dumb graphic is deleted and replaced, my design geometry may lose its rule but it's still there, but elements designed from it are fine. There's no GOOD way to do this that I've found (and I'd LOVE to here more approaches) but creating a file with my "design copy" ruled to the older graphics seems to be getting us by.

I know that this isn't the answer you want, but if I was in this situation... after making it super clear to my superiors that I could do the 3D modeling in the older software faster/better/cheaper and getting shot down, I would just accept that I need to add a couple steps to my workflow where I create and/or update a separate ORD DGN with featurized versions of the "dumb" linework. Instead of using Point Controls which would be tied to specific elements that might change as I make revisions (unless I use a Complex Redefine), I would consider assigning a Horizontal Feature Constraint in my template to the points that I want to control.