Starting in Vectorworks 2018, users can now create menu commands defined by Marionette networks.
To do this, select a wrapper in your file, right click, and choose "Convert to Menu Command..."
This will open a dialog window where you can name this command. A background process will save your Menu Command to a file in your User Folder.
Once that's complete, you can access the menu command by navigating to Tools > Marionette Commands > [YOUR COMMAND HERE]
This menu command will allow users to select an object and create a class defined by the current object's attributes.
v1.0 will set the following. There are plans for improvement.
If there's an attribute you need/want right away, let me know, and I'll do my best to get it in.
One note: the new class will not be set to "Use at Creation," this must be set in the Edit Class dialog.