I (like presumably many others) have built something similar. My main difference though is that the critics operate on each stage of development before it can move onto the next. The stages are defined by deliverable artifacts: issue, plan, pull request. Critics must approve each artifact before you can move onto the next. So the process is defined by a DAG which defines how to transition successfully from one artifact to the next. It's been fun to work on and I would like to open source it soon, but I assume many others are working on similar systems.