I personaly think the E-mail track and trace feature should be available to all licences, as this is a quite simple feature that makes life debugging e-mail issues so much better than having to inspect mail logs manualy.
For other features, I do agree with having them in the pro pack (like the resource limiting), but features usefull to small system admins (like the e-mail track and trace) should be available to everyone.
For other features, I do agree with having them in the pro pack (like the resource limiting), but features usefull to small system admins (like the e-mail track and trace) should be available to everyone.