It would be nice if the User Text values could be more akin to the Grasshopper inputs. For example, I might want to have a boolean checkbox, a value list or number slider (with type input). This way, User Text could become a more integral part of the workflow where Rhino geometry + attributes drive a Grasshopper script.
With value lists, I can envision there being a central place to edit the list of possible values for a particular User Text attribute (e.g. wall types). Any geometry that has shares this Attribute key could in turn pick from the predefined values (e.g. masonry or timber frame). Additionally, it could enable type prediction/ correction which prevents users from typing a non-existent value.
With such functionality built into Rhino, one can make Rhino work more akin to Revit for architecture.