Thank you for the really great plugin! I am actually looking for something similar.
I would like the plugin to operate similar to your shopping cart. and the site will have a number of tourist map locations to visit. Each location post/page has a button "bucket list" that would add that location to a 'shopping cart' like list. A visitor could add the locations they want to visit by pushing the button to update the list and save and/or email the list to the admin and themselves.
Can you make something like that?