Get the top 500 unique referring domains (1 link per domain)
Check your anchors optimization, see how authoritative your links are, check your follow/nofollow ratio, view your links distribution.
Audit your own domains to see how you are doing with linkbuilding.
Look at your anchor text distribution to check if you have not over-optimized or under-optimized your backlinks' anchors. If you are using too many "money keyword" in your anchor you can be penalized by search engines.
The Trust Flow and Citation Flow distributions give a very good idea of the quality of your backlinks. The goal is to get backlinks from more authoritative websites as your own websites gains authority.
Audit your competitors'domain to see how you compare with them and learn new linkbuilding tactics.
Just looking at your competitor backlinks can give you a lot of ideas on how to acquire backlinks. Analyze carefully their backlinks strategy and try to replicate them.
only 59¢ per report