Anybody who uses Dynamo runs into this problem at some point, Editing Groups.
I’m talking about adding elements to groups, changing family types, changing builtin instance parameters that can not be changed to “can vary by group instance” like Unconnected height or Base Constraint.
these are all not posible right now.
Ungrouping and Regrouping is not an option because of all the Attached Detail Groups, Dimensions and other Annotations that would be lost.
So please upvote this Idea to add group editing to the Revit API, and lets hope it makes it to the Revit Public Roadmap.