RICE and BRADY are free, and they will stay free. No paywall, no account, no paid tier. It is all built from free public data.
Most of the work was tests that failed: four other ways to rate teams, four ways to pull a passer apart from his team, and a long list of ideas that seemed right and did not help. What you see is what held up on games the model had not seen.
If you find it useful and want to help pay for the time, the button below does that. It changes nothing about what you can see.