One number that can't be gamed: your skill against the crowd, bounded by how much you've actually predicted.
Each resolved pick scores how much you beat the crowd's consensus, so calling a 55/45 upset is worth far more than a 92/8 lock. Scores are shrunk toward zero until you've built a sample, then bounded by a 95% confidence interval — so a hot streak of ten picks can't leapfrog a proven record of five hundred.