Generally this is a cumbersome and amateur set up. To create a new Wall Type, one needs to first duplicate an existing wall type.
When managing wall types, redundant types must be purged using PU command.
A pop-up dialogue for managing Types should be modernised more akin to the Materials pop-up which has been a staple part of Revit for years. This is a decent manager allowing quick editing of Types with visual cues and centralised bank of assets/properties to incorporate.