A 35%-accurate model that still ranked well, and adding more features made it worse (point-in-time equity backtest) [P]

I built a calibrated predictive model on point-in-time fundamentals and two results surprised me enough to write up. Sharing the project and the method, happy to have the methodology picked apart. Setup: ~250 S&P 500 companies graded from their 10-K filings on qualitative factors (moat, market position, leadership, capital allocation). Grading is point-in-time, the grader sees only the filing for that vintage, across 2014/2017/2020. Index membership r