It would be nice to see new feature like mark messages with number of attachments = >2. To do this just use Message Filters from menu, when click "new" and in drop down menu (subject, body, date etc.) select new feature called for example number of attachments. When set Tag Message RED.
Why I need it? I mainly get emails with attachments and sometimes I don't noticed that I get 2 attachments and I use only first, forgetting about second.