The Subscribers tab in Insights shows you a lot of information about individuals' engagement and settings.
By clicking on a subscriber's name in the Individual Subscriber Metrics table, you're given a brief snippet of that user's information, including their Delivery Settings, the date they subscribed to your Cerkl, their last newsletter delivery, the date they personalized (if they haven't, this info will not appear), the Segments they're included in, and their Top 5 Interests.
A note on the Top 5 Interests attribute: These are your subscriber's top five favorite organizational categories based on their engagement (which is scored right behind the category), both explicit and implicit interests. The more a subscriber clicks on material that's tagged with a certain category, the more the score rises. In the example above, Joe has clicked on stories tagged with "Generating Content" more than any other category.
This will allow you to troubleshoot your subscribers' issues if they were to contact you.
These insights can be personalized even further with a Custom Dashboard.