We're also building our own model, for slides that actually look designed, and the hardest part was defining what "looks designed" even means. In the end we set

We're also building our own model, for slides that actually look designed, and the hardest part was defining what "looks designed" even means. In the end we settled on a verbal definition of roughly "image-heavy" and "looks like a magazine spread," and then had no choice but to have humans label by feel. That was manageable for us. Video sounds genuinely hard though: more senses involved, and I'd guess the variance is far larger.