Adding expansion modules is something we have been discussing since our first dev meeting on access control, as it is obviously a significant architecture choice. We did ultimately decide to initially keep the option more simple, for IP door access controllers, so that the design models/UI could be evolved over time.
That being the case, is it possible to add a manual door count override? If 16 doors are being cabled back to a single location, and the base controller is a 4-door model, the need for the additional 3 controllers all within the same physical space makes the map get cluttered quickly.
I suppose stacking the controllers precisely on top of each other is a way around this, but it makes them harder or impossible to access unless from the list view.
How often would you be switching the controller that a door is wired to, in your design process? Are you balancing large numbers of multi-door controllers, so they would be effectively wired to the same cabinet, just a different controller in that cabinet? Or something else?
In the first and only example I have of using the new access control features on Designer, I am planning a school. Very old building, oddly shaped and difficult to cable. There's a group of roughly 16 doors that we are considering the cost/benefit of running all to one closet vs utilizing a second IDF/distributed controller. After starting with the single closet option and assigning doors to controllers sequentially, I quickly realized that the doors/controller assignments could not be split out to multiple closets in a way that made sense on the physical layout without nuking the doors and starting over.
Ultimately, I reverted to the old way we've been using Designer for access control - cabling intercoms to closets and naming them "Door 1", "Door 2", etc. This way, we can quickly disconnect a "door" from a closet and associate it with another.