In regards to your addition in 2017...
"you by adding the PointObject attribute last update, this records the object id of what the point was added to,"
I've not had a chance to look at 2017... however, this might push me to do so soon.
Is there option in place yet to tell APL to use this PointObject attribute in APL Renumber and other functions. Namely to Push Renumbered Revised Point data back to the MEP Property Set like "Export Point # to Property Set Field" does when the point is first established? ... other related question: Are you using the ObjectID and not the Entity Handle? As I understand it... the ObjectID never changes but the Entity Handle could possibly change.
This single improvement would go a long ways to mitigate issues we have where our Point number in our Hanger Fab Data gets out of sync with Total Station Data. We constantly have to make certain to spot check the points in hanger fab agrees with point number annotation.
(We are pretty new to Revit... but it would be well I think to do this there too)