Something that could be interesting is processing all videos in some subgenre, like say "game development", rank them by popularity, summarize them, and then analyze for patterns. This would be valuable information for anyone wanting to make a video with higher chances of being shown to people.
Or one could not do that and focus on quality instead.
That was actually my initial thought for what I would test with a tool like this. How much does quality matter?
Quality of course has many definitions, but in the light of this tool, the measurable quality could be "how much novel information does this video have?" I'd hope a trend that pops out is that content with more information around a focused topic would perform better. But as it is, I only have my personal preferences and my suggestions list (based on my personal preferences) to go by.
I'm not a content creator myself, but if I was, I might find this kind of analysis interesting enough to pay for.