Hm... A "Good Nicks" function would be nice. The owner can add "Good Nicks" and there can be a mode named "Nick Type" or "Nicks Allowed" that can have the options; "Good Nicks", "No Bad Nicks", and "All Nicks". Where "Good Nicks" only allows nicks on the "Good Nicks" list in, "No Bad Nicks" allows anyone in unless they're on the "Bad Nicks" list, and "All Nicks" allows everyone, regardless of list.
Also, what's the specifications for "Flood Protection"? And you did not answer the question regarding "Revolving Door".