Overhaul WordPress Comment System

I’m sitting on a WordPress site with a lively readership but a comment backend that’s buckling under 4,000 items in the moderation queue. Real discussion is drowning in spam and our editors no longer bother opening the queue... (Budget: €10000 - €20000 EUR, Jobs: API Integration, Data Analysis, Database Management, MySQL, PHP, Usability Testing, Web Security, WordPress)