I think you should do 2 or 3 games per video. Your content is for education and you do it well. With longer form content, you'll have more engagement. It was gimicky and fun when you were doing the coloured rengar videos but these types are better suited for longform imo.
Generally these vids range from 10-17 min, and I will be focusing on the second half of this climb when I'm playing in elo where I feel I can teach more - Some episodes will have more than 1 game!