Ok
Here's what I think I'll try. One song every 2 weeks, no exceptions. Appoint another couple of mods so the existing team never feel overwhelmed. Rename the reviews forum to something like Feedback on finished songs and create a new board called feedback on works in progress.
Additionally to this, I'll amend the guidelines for posting, asking people to be specific about the feedback they're looking for, tell us about their goals, make the reviewers' lives easier, always post the lyrics in the thread.
I know people mess up occasionally, but this gives us the basis to remove threads when it's clear people haven't bothered to learn about our community first.
Then in a month or 6 weeks time, we'll reconvene and see how it's going?