It's easy to query this registry value with something like Inno Setup and use it as a default value when prompting the user for the plugin directory. It would help a lot if plugins and/or mappacks would use this value as the default value for the plugin directory and for sure allow the user to choose another path but for the unexperienced computer user it would make things easier
If someone wants an example for Inno Setup I could post it here. It's just something I noticed.
Between, thanks for the Mods [&o]