I have not been able to find any answers to this in this forum or in the larger web, so I do not know if it is possible in Architect. It is a trivial thing to implement in Ext.js but can see no route to it in Architect. The "create override" button seems to be a possible path, but I cannot find any documentation on what this is actually used for or how to implement it.
The purpose in this is that I would like to have a custom base controller class, say for a page controller, which I can then extend as needed, eg for the homepage behavior. While there may be little shared behavior between the instances, it would be nice to not have to add a getPageName method to each by hand.