Every network is different, and tuning your Nessus scan policy can yield great results. A new plugin has been added for Nessus 5.2 and higher (plugin ID #66359) which will analyze the scan results for your environment and the scan settings that were used, and then suggest improvements for a better audit.
For example, I scanned a Windows system on the network without entering credentials. When the Nessus scan was complete, I was presented with a "tip" that, if implemented, would yield more complete vulnerability scanning results:
Tips appear automatically once your scan completes. The initial set of tips will include several different recommendations. For example, if the targets presented network-based services and no Windows credentials were entered, a tip is displayed along with a link to instructions on how to add credentials. You can read the recommendations page titled "How to Enable Credentialed Checks on Windows" as an example. Or, if a Microsoft Exchange server is detected on your network, Nessus will remind you it could be configured to perform a mobile device scan.
Nessus tips will help users configure their scans to provide more complete and actionable results. As we continue to add more features into Nessus, more tips will appear after your scans if they make sense in your environment.